HOME LIGHTING DESIGN GUIDE Energy Efficiency Reference Guide DISCLAIMER: Neither CEATI International, the authors, nor any of the organizations providing funding support for this work (including any persons acting on the behalf of the aforementioned) assume any liability or responsibility for any damages arising or resulting from the use of any information, equipment, product, method or any other process whatsoever disclosed or contained in this guide. The use of certified practitioners for the application of the information contained herein is strongly recommended. This guide was prepared by JEM Energy Inc. for the CEATI International Customer Energy Solutions Interest Group (CESIG) with the sponsorship of the following utility consortium participants: Home Lighting Design Guide CEATI Report No. T081700-7034 Prepared by: JEM Energy Inc. Calgary, Alberta, Canada Principal Investigators: H. David Miller, Principal, JEM Energy Inc. Calgary, Alberta, Canada Kevin Hooper, P.Eng., LEED AP Principal, Lighting Solutions Inc. Calgary, Alberta, Canada © 2009 CEATI International. All rights reserved. ABSTRACT This is a practical guide, designed to provide information on home lighting technology that will improve efficiency opportunities through a designed approach and understanding of components and technologies that are commercially available. This is essential reading for all levels of the residential design and construction process, both for new and renovation projects. Home-owners, trades people, interior designers, architects or educators will find information of value in this Guide. Key Words: Home lighting, efficient residential lighting, functional and effective lighting, efficient lighting design. ACKNOWLEDGEMENTS The investigators wish to thank the CEATI Technology Coordinator Phil Elliott, as well as Project Monitors Roy Hughes of BC Hydro, Sean Quigley of Manitoba Hydro, Eric Witkowski of Manitoba Hydro, Gary Tollefson of SaskPower, Rebecca Fiissel of SaskPower, Tom Seimer of Hydro One, Katherine Delves of NRCan, and Uon Vuong Wang of Hydro Quebec for their support and guidance. The following manufacturers have graciously provided pictures for inclusion in this publication: American Fluorescent Canlyte Cooper Lighting CREE LED Lighting Solutions CRS Electronics Dolan Designs General Electric Company GVA Lighting Jesco Lighting Juno Lighting Kichler Lighting Leviton Magic Lite Nuvo Lighting Oligo Lighting OSRAM Sylvania Philips Lighting Progress Lighting Satco Lighting Sunscope TCP Ushio World Imports The authors also appreciate the valuable input from the following contributors: Randall Whitehead from Randall Whitehead Lighting for a variety of photographs. Jane Eastman-Miller for editing services. Susan Matheson from Susan Matheson Interiors and Kelly Inglis from Robinson Lighting for input on residential lighting design and fixture selection. The California Lighting Technology Center for floor-plan suggestions. EXECUTIVE SUMMARY Light, at its most basic, makes all things visible. In ancient times, people relied on the sun, stars and moon to light their way, do their work and keep them safe. Fortunately, we have many more options available today! Good lighting can make our homes comfortable, functional and fun places to be, where art and architecture look great and friends and family love to visit. Our lighting can be both effective and efficient. Effective so it can evoke a mood, light a task or provide security. Efficient so we can get the effects we want but still be mindful of our energy use. Effective and efficient residential lighting requires a mix of artistic and scientific skills. Proper lighting can enhance task performance or aesthetics. Poor lighting can waste energy, make tasks difficult to perform and even result in adverse health effects. It’s important to learn how to create a lighting system that is efficient through proven design techniques combined with appropriate technology chosen from the myriad options on the market today. What makes a room comfortable, a home inviting, a landscape interesting? How does light affect colour? What types of fixtures are used for which areas? How do you determine energy costs associated with various types of lighting? What are all the questions that need to be answered to create good home lighting? We know we want the lighting to be done right but what does ‘right’ really mean? This Home Lighting Design Guide is intended as a resource for homeowners, builders and designers who are willing to invest some time and money in effective and efficient lighting to discover the ‘right’ residential lighting. It answers the common lighting questions----and even some uncommon ones----and incorporates proven design techniques with energy efficiency opportunities throughout all areas of a typical home. We believe this is essential reading for all levels of the residential design and construction process, both for new and renovation projects. Whether you’re a home-owner, tradesperson, interior designer, architect or educator, we believe there is information here for you. TABLE OF CONTENTS ABSTRACT .......................................................................................................................... iii ACKNOWLEDGEMENTS........................................................................................................ iv EXECUTIVE SUMMARY .......................................................................................................... v 1 a. b. c. d. e. f. g. h. WHAT SHOULD I KNOW ABOUT LIGHT AND COLOUR? ............................................... 9 What is light? ...................................................................................................................... 9 Colour Mixing ..................................................................................................................... 9 How we see colour ............................................................................................................. 10 Using CCT and CRI ............................................................................................................ 13 Daylight and Full Spectrum ................................................................................................. 14 How is light measured?....................................................................................................... 15 How do light and surfaces interact? ..................................................................................... 15 Why do we see what we see? ............................................................................................. 16 a. b. WHAT ARE OUR SOURCES OF LIGHT? ...................................................................... 19 Lamp Characteristics .......................................................................................................... 19 What are the lamp categories? ............................................................................................ 22 a. b. c. d. e. f. g. h. i. j. k. l. WHAT ARE THE OPTIONS FOR LIGHT FIXTURES?........................................................ 31 Surface ............................................................................................................................. 31 Pendant............................................................................................................................. 32 Recessed ........................................................................................................................... 32 Track ................................................................................................................................ 33 Portable ............................................................................................................................ 34 Landscape ......................................................................................................................... 34 Fibre Optic ........................................................................................................................ 35 Daylighting ........................................................................................................................ 35 Accessories........................................................................................................................ 36 Efficiency ........................................................................................................................... 36 Fixture selection criteria ...................................................................................................... 38 Exterior considerations ....................................................................................................... 41 a. b. c. d. WHAT ARE THE PRINCIPLES BEHIND GOOD LIGHTING DESIGN? ................................ 43 Light layering ..................................................................................................................... 43 Wall Washing, Silhouette and Grazing ................................................................................ 46 Visual priorities .................................................................................................................. 48 Control systems .................................................................................................................. 48 a. b. c. d. e. f. g. h. WHAT ARE SOME PRACTICAL LIGHTING CONCEPTS FOR MY HOME? ........................ 53 Entry Ways and Hallways ................................................................................................... 53 Living Room ....................................................................................................................... 54 Dining Room...................................................................................................................... 57 Kitchen .............................................................................................................................. 60 Bedroom ........................................................................................................................... 63 Bathroom .......................................................................................................................... 66 Family/Great Room ........................................................................................................... 69 Home Office ...................................................................................................................... 71 2 3 4 5 i. j. k. l. m. Stairwells........................................................................................................................... 71 Garage ............................................................................................................................. 73 Laundry Room ................................................................................................................... 74 Exterior Deck ..................................................................................................................... 74 Landscape ......................................................................................................................... 76 APPENDIX A. GLOSSARY .................................................................................................... 79 APPENDIX B. ENVIRONMENTAL IMPACTS OF LIGHTING ENERGY EFFICIENCY ........................ 87 1 What I Should Know About Light and Colour 1 WHAT SHOULD I KNOW ABOUT LIGHT AND COLOUR? a. What is light? Every second of our lives, we are surrounded by a wide variety of unseen energy. Radio waves are picked up by our car radios, unseen signals link our cell phones----at least most of the time, ultraviolet radiation turns us red at the beach, and satellites beam TV signals directly into our homes. More powerful and carefully controlled versions of this energy provide us with x-rays at the hospital and heat our food with microwaves. All this energy is called electromagnetic radiation, or simply radiation. It comes in a variety of frequencies and travels at the speed of light. Visible light is also electromagnetic radiation but is limited to that narrow band of frequencies that the human eye can detect. Our eyes are tuned to these frequencies, just like a radio is tuned to radio waves. Each frequency within this range of light is interpreted by our brain as a different colour. Just outside our visible range is infrared radiation, at a slightly lower frequency than red light. Our skin is sensitive to infra-red and we feel it as heat. At the other end of the range is ultra-violet radiation, at a slightly higher frequency than blue light and also invisible to the eye. Consequently, it is technically incorrect to refer to ultra-violet radiation as ‘ultra-violet light’, since it is actually invisible to the human eye. 9 Figure 1-1 Radio waves, infrared heat and light—it’s all ‘electromagnetic radiation’. The human eye is only sensitive to a narrow band of frequencies we call ‘Light”. Courtesy: General Electric Light travels in a straight line until it is bent, reflected or absorbed. If, on its straight line path, it happens to enter our eyes, we can see it but, until then, it is invisible as it passes through the air. For example, if you point a flashlight away from yourself, you can only tell it’s turned on if it hits a reflective surface somewhere, or reflects off fog or dust in the air. b. Colour Mixing Most of us know the three primary colours of paint as red, blue and yellow, which can be mixed to create other colours. If red and blue paint are mixed, they produce purple; blue and yellow mixed produce green and so forth. Mixing all three colours ends up a dirty brown. This is called Subtractive Colour Mixing. Light does not act like paint and, in fact, even the three primary colours are different! The three primary colours of light are red, green and blue. The first colour computer monitors available were ‘RGB’ as a result. When red, green and blue light are mixed, it doesn’t turn dirty brown, it turns white! You can actually try this 1 What I Should Know About Light and Colour at home with three coloured floodlights. Shine all three onto a white wall and the wall will look white. In the same way that white light can be split into a rainbow of colours through a prism, those individual colours can be re-combined to create the original white light. We recognize seven different colours when white light is split, often remembered by the ‘Roy G Biv’ memory trick: red, orange, yellow, green, blue, indigo and violet. These are what we see when light from the sun is split by droplets of water into a rainbow. 10 Figure 1-2 Light and paint do not mix the same way – even the three primary colours are different! Courtesy: OSRAM Sylvania c. How we see colour We mentioned that light must enter our eyes to be seen. This usually happens when light bounces off walls or other objects. If an object is white—and our light source is white—the object will look white. However, if the light source is red, then the object looks red because there are no green and blue frequencies to mix with the red to create white. Similarly, if the object is red and the light source is white, we see only red. Even though the source is providing green and blue light, these frequencies are absorbed by the paint and only red light is reflected. This is why we have colour—various surfaces absorb some frequencies and reflect others. To summarize, in order to see a particular colour reflected off an object, the light source must contain that colour and the object must reflect only that colour. 1 What I Should Know About Light and Colour Figure 1-3 The vase looks red because the other colours contained in the white light are absorbed, while red is reflected. Under a blue lamp, the vase would look black. Courtesy: OSRAM Sylvania Colour Terms We use two key terms in the lighting industry to describe colour: Correlated Colour Temperature (CCT) and Colour Rendering Index (CRI). Correlated Colour Temperature (CCT) Imagine an incandescent lamp on a dimmer, turned almost off. Even though it is not glowing, we may still feel the infra-red heat. If the dimmer is turned up, the tungsten metal filament begins to glow a deep red. The filament is radiating mostly infrared heat and a little visible light. As the filament is heated further, orange, yellow, green and blue frequencies are added. Once it gets hot enough, all the colours of the rainbow are mixed and the metal is ‘white hot’----that is, producing white light. CCT is simply a way of describing how red or blue a source looks using the Kelvin (K) temperature scale, which is close to Celsius (C) at these high temperatures (0° K = -273° C). The common 60W lamp filament operates at about 2700° K, so it produces a lot of red light but very little blue. Fluorescent sources can be made to look whiter, or even blue, by using various chemical coatings. Figure 1-4 An incandescent lamp works by heating up a tungsten-metal filament using electricity. It is red when dimmed, but becomes whiter when other colours (frequencies) are added at full output. Courtesy: OSRAM Sylvania 11 1 What I Should Know About Light and Colour We have come to think of red, orange and yellow as warm colours and green, blue and violet as cool colours. These are psychological terms, not to be confused with the actual temperature of the filament. Figure 1-5 We think of red, orange and yellow as ‘warm’ colours and green, blue and violet as ‘cool’ colours. Colour Temperature is the mood setter for a room. Warm colours create a comfortable and attractive ambience. 12 Figure 1-6 Notice how the blue ball cap lit with a warm lamp looks almost black, since there is very little blue content. However, when lit with a cool source, the red ball cap loses a bit of its intense colour but the blue is vibrant. Courtesy: OSRAM Sylvania Colour Rendering Index (CRI) CRI is a scale to 100 which describes how well colours are rendered under a particular source. Incandescent lamps, including halogen, are 100 on the scale, however fluorescent sources and LEDs range from 70 to 100. The higher the number, the better the colours are rendered, and 80 is usually the minimum recommended CRI for use in homes. Figure 1-7 indicates a low CRI on the left and the one on the right with a lighting source with a CRI greater than 80. Figure 1-7 A higher CRI source will provide more vibrant colours. Choose a source with a CRI of 80 or higher for good colour rendering. Courtesy: OSRAM Sylvania 1 What I Should Know About Light and Colour d. Using CCT and CRI First, choose the CCT. Most people prefer warm colour sources in their home, so choose a source of 2700° K 3000° K. This is usually marked on packaging. Incandescent lamps are in this range. Second, choose the highest CRI you can find. Halogen sources are already 100, however compact fluorescent sources, in particular, should be chosen above 80 CRI. Basement remodel example Let’s put all the previous information together into a practical example: a basement remodel. Let’s say 3000° K halogen and compact fluorescent sources are chosen. Next, you head to the store to pick out carpet and paint but you don’t trust the store lighting to be ‘accurate’. What do you do? Most people walk to the nearest window to find out the true colour under daylight. Will the carpet and paint look the same in your basement? No! Daylight provides a different mix of colours than the sources we use in our homes. Your colour choices could look completely different when installed. Always try to find a light source similar to the one you will use in your home when choosing products at a store. 13 Figure 1-8 Incandescent sources provide a rich blend of warm colours but are weaker in blue colours. Courtesy: Philips Lighting Figure 1-9 Fluorescent sources provide a variety of colour temperature and colour rendering options, but with some colour gaps, and therefore a CRI of less than 100. Courtesy: OSRAM Sylvania 1 What I Should Know About Light and Colour e. Daylight and Full Spectrum Daylight and Seasonal Affective Disorder (SAD) Daylight contains all the colours of the rainbow in very intense quantities (100 times or more than indoors). The actual colour temperature of the sun is about 6500° K; however the blue sky can be 10,000 -- 20,000° K! Our bodies are tuned to daylight and we thrive on the bright levels and variety of colours that we experience outside. Daylight is also dynamic, changing with cloud cover and time of the day and year. The ability to see through a window or receive light from a skylight during the day has been shown to provide significant mental and emotional benefits. The incidence of Seasonal Affective Disorder (SAD) grows the further north one lives and is prevalent in the winter when exposure to daylight is limited or, at times, non-existent. Those suffering from SAD should be treated under a doctor’s supervision. Exposure to bright light with some blue content in the morning has been shown to improve symptoms. However, in general, this is not an appealing approach to lighting a home and is typically achieved with portable light fixtures. 14 Figure 1-10 Daylight provides a wide spectrum of very intense visible and non-visible (UV, IR) radiation, which is beneficial both physically and mentally with appropriate care taken for eyes and skin. These conditions cannot be recreated in our homes with ‘full spectrum’ sources. Courtesy: General Electric Company Full spectrum lighting Over the past 20 years, the term full spectrum lighting has been aggressively marketed as somehow better or healthier or natural. ‘‘Full spectrum lighting’’ is actually a marketing term, with no scientific definition, that refers to high colour temperature fluorescent sources, typically 5000° K or above. As a result, these sources appear bluish-white in colour. Some extraordinary claims have been made about the benefits of full spectrum sources. Over time, most of these claims proved to be false or greatly exaggerated. However, enough publicity was generated to create a demand for cool sources, which are widely available today. 1 What I Should Know About Light and Colour Light sources in the 5000° K range have been shown to make reading and small tasks easier, so they are a reasonable option for a task or reading light. From an aesthetic point of view however, these blue-rich sources can be quite unattractive. People tend to like warmer colours at lower levels (sunrise and sunset for example), and cooler colours at very high light levels (outdoors, mid-day). Be careful about investing in 5000° K fluorescent lamps before trying out one or two. If you don’t like the appearance, don’t use them. They are no healthier for you than a warmer source. f. How is light measured? While it is beyond the scope of this guide to describe complex lighting terms, a summary of the four most common units of lighting is useful in understanding lighting concepts. (More terms are available in the glossary at the back of this Guide.) Flux A term used to describe the total quantity of light flowing out of a source. It is measured in lumens, found on most lamp packaging. It can be thought of as a ‘gallons per minute’ type of measurement and is useful when comparing two different sources. Illuminance This term, often called the light level, refers to the total number of lumens falling in one square foot. It is measured in footcandles (fc). In metric form, it is expressed as lux, which is lumens/sq m. 1 footcandle = 10.76 lux. For example, if you directed all the light from a 15W compact fluorescent lamp (about 600 lumens) onto a kitchen table that was 1.4 sq m (15 sq ft), the total illuminance would be about 600/15 = 40 footcandles (or 430 lux). As a reference, a typical office is lit to 40 -50 fc, whereas light levels outside on a sunny day can exceed 5,000 fc. In homes, light levels range from 1fc in a very dim room for TV watching, to 75fc on a kitchen counter with under-cabinet lights. Luminance This is what we actually see when light is reflected from a surface. It is simply the illuminance multiplied by the reflectivity of the surface. It is measured in candela/sq ft or candela/sq meter. Intensity This refers to the apparent brightness of a small point of light when looking from a certain angle and is measured in candelas. If you look directly at a reflector style lamp, it appears brighter than if you stand at 45° to it, so the measured intensity would be higher. g. How do light and surfaces interact? Light can be transmitted or refracted (changed direction) through water or glass. Most objects absorb light of various frequencies, but the light that is reflected is what we see. The terms matte or gloss are familiar to us when it comes to paint because of how different they appear. This is actually a function of how light is reflected from surfaces. There are three types of reflection: diffuse, specular and semi-specular. 15 1 What I Should Know About Light and Colour Diffuse, Specular, Semi-Specular Objects can transmit or reflect light in a diffuse manner. For example, a white piece of paper or a sandblasted window will reflect light in all directions. However, if you shine a flashlight on a specular (mirror-like), it will bounce off. Semi-specular surfaces combine diffuse and specular properties. This is the case, for example, with many brushed metal surfaces. Be careful of specular and even semi-specular surfaces, as they can cause glare, for example, from under-cabinet lights. Diffuse surfaces help provide good ambient light, and there is more on this in Section 4. Figure 1-11 The top is specular, like a mirror. The middle graphic is semi-specular, like brushed metal and the bottom is diffuse, like white paper. 16 h. Why do we see what we see? The human vision system is incredibly complex and adaptable. Given enough time to dark-adapt, one can read by the light of a few stars and yet function comfortably in bright sunlight, literally millions of times brighter. The eye can detect movement miles away, yet read fine print held at arms’ length. Biology of the eye The eye collects light, partially processes it and sends signals to the visual cortex at the back of our brain for further processing and interpretation. The resulting signals sent to the brain are so complex that, for the blind, it is not possible to simply use sensors such as those used in digital cameras to replace the eye. Light is focused by the lens onto the retina, the data gathering part of the eye. The pupil provides some protection by adjusting quickly to particularly bright conditions. The retina continually adjusts its sensitivity to bright or dark conditions and to colours. It can take up to 30 minutes to adapt completely to a dark environment but a fraction of a second to extremely bright locations. The retina is filled with receptors called rods and cones. Rods provide sensitivity to surface brightness and movement but not colour. Cones are very sensitive to colour and, not surprisingly, there are three types: red, green and blue. More recent research has shown that there is also a fifth receptor, which sends signals to our hypothalamus, where it oversees the function of our body clock. Melatonin production is regulated in this process, which has a direct impact on our wake/sleep cycles. It is well known that exposure to bright light (more than we get inside our homes or offices) towards the blue end of the spectrum is required each day to reset our body clocks properly. 1 What I Should Know About Light and Colour Figure 1-12 Cones detect red, blue, and green frequencies. An object’s colour is most intense when we look directly at it. Rods detect brightness and movement. We see movement best in our peripheral vision. Courtesy: General Electric Company Age and seeing As we age, our eyes need additional light to make up for losses that occur in the vision system. We require as much as double the light by the time we reach 50 as we did when we were 20. However, we also become more susceptible to glare, so we need the extra light to be diffused and shielded so we do not see the source directly. What factors affect our ability to see? There are four primary factors that influence our ability to see clearly: size, luminance, time and contrast. The size of an object clearly affects our ability to see it. However, luminance (surface brightness) is critical as well. For example, a small chair in a dim hallway may need to be lit to keep from stumbling over it. Time plays a role in vision if, for example, we are driving and have a limited time to focus on and register an object. Finally, contrast between what we are focusing on and the immediate background will allow us to see it much better. For example, we cannot see black letters glued onto a dark blue wall very well or a yellow object against a white wall. More light can help one see low-contrast tasks better, for example using light coloured thread on light coloured material. Light letters on a light background are difficult to see Dark letters on a light background are easier to see Figure 1-13 In order to see an object or text well, there must be good contrast between what we are trying to see and the immediate background. What is glare? As mentioned, glare becomes more of an issue as we age. There are two primary types of glare----discomfort and disability. 17 1 What I Should Know About Light and Colour Figure 1-14 Disability glare is primarily due to light reflecting off computer screens or glossy magazines, ‘washing out’ the text. Actually, by reducing the contrast between the letters and the background, as shown, it is difficult to read. Figure 1-15 Discomfort glare is when our eyes, often in our peripheral vision, pick up a very bright source of light. This could be from a window or a direct view of the lamp inside a light fixture. Our eyes continually try to adjust to this bright spot by adjusting pupil size, causing muscle fatigue and eye strain. From this brief discussion of lighting fundamentals, there are clearly many things to consider when choosing the right lighting. Read on as we take you through the various lighting sources in the next section! 18 2 What Are Our Sources of Light? 2 WHAT ARE OUR SOURCES OF LIGHT? Entire books have been generated on this topic alone -- complete with onerous detail. This chapter tends towards practical advice rather than pages of theory. We generally use the term lamp or source for all types of light-emitting products used in light fixtures to produce the light we need. These can range from Light Emitting Diodes (LEDs)---- that are almost too small to see----to 4-foot long fluorescent tubes. Figure 2-1 The number of available sources grows each year. Incandescent and fluorescent are the most common for home use. Courtesy OSRAM Sylvania Every lamp has a variety of characteristics that help determine the most appropriate one for each application. When choosing a light source, we may be tempted to ask for the ‘most efficient’ or the ‘best Colour Rendering Index’. However, various sources lend themselves to certain applications (task, ambient, accent, decorative---more on this in Section 4). Choosing an appropriate source for an application requires knowledge of the pros and cons of each. a. Lamp Characteristics Following is a brief description of the most important characteristics to evaluate. On the next page, you will find a summary of various lamp types and their characteristics. Efficiency and Efficacy Efficiency is actually a term that refers to the light output of a light fixture in relation to the light output of the lamps, i.e. how much of the light is being trapped in the fixture. Efficacy refers to the lamp itself and is a measure of how much light (lumens) is being produced for each watt of power delivered to it. This is measured in lumens/watt (LPW). Depreciation All lamps lose some light output over their lifetime, ranging from 5% to over 50%. This depreciation must be considered when a lamp is first installed by allowing for extra light. 19 2 What Are Our Sources of Light? Lamp manufacturers usually provide two lumen levels for a particular source, initial and mean. Initial lumens, as the name suggests, are produced when first installed. Mean lumens are the approximate lumens produced at 40% of the rated lamp life. So, if the rated life is 2,000 hours, the mean lumens would be the output after 800 hours of use. Life The rated life of a lamp is stated in hours and represents the expected time for 50% of a group of these lamps to burn out. Source Comparison Chart Table 2-1 is meant to be a quick reference when comparing various types and wattages of lamps. How long do they last? How efficient are they? Where do I apply them? Note that significant variations are available from different manufacturers. 20 Type Description Volts Power (W) Lumens (Mean) Efficacy (LPW) CCT (°K) Rendering (CRI) Life (hrs) Applications (Refer to Section 4) Standard Incandescent Halogen Incandescent Compact Fluorescent Halogen Incandescent Standard A19 Standard A19 Spiral G9 Bipin 120 120 120 120 60 60 15 60 600 800 760 830 10 13 51 14 2700 2900 2700 2900 100 100 80 100 1,000 3,000 10,000 2,000 Accent, Task, Decorative Accent, Task, Decorative Ambient, Task Task, Decorative Halogen Incandescent Halogen Incandescent Halogen Incandescent Halogen Incandescent Halogen Incandescent Halogen Incandescent Halogen Incandescent MR16 MR16 MR16 Par16 GU10 Par 20 Par30 Par38 12 12 12 120 120 120 120 20 35 50 50 50 50 50 (1) (1) (1) 500 550 660 700 14 14 14 10 11 13 14 2900 2900 2900 2700 2700 2800 2800 100 100 100 100 100 100 100 4,000 4,000 4,000 2,000 2,500 2,500 3,000 Accent, Task Accent, Task Accent, Task Accent, Task Accent, Task Accent, Task Accent, Task Compact Fluorescent Compact Fluorescent Compact Fluorescent Compact Fluorescent Compact Fluorescent Spiral Spiral Spiral Spiral Triple Tube 120 120 120 120 (2) 10 15 20 42 26 420 760 965 2160 1500 42 51 48 51 58 2700-4100 2700-4100 2700-4100 2700-4100 2700-4100 80 80 80 80 80 10,000 10,000 10,000 10,000 12,000 Ambient, Task Ambient, Task Ambient, Task Ambient, Task Ambient, Task Full Sized Fluorescent Full Sized Fluorescent Full Sized Fluorescent 4' T8 4' T5 Circline T5 (2) (2) (2) 32 28 40 2950 2400 2800 92 86 70 3000-5000 85 3000-5000 85 3000-4100 82 25,000 Ambient, Task 24,000 Ambient, Task 12,000 Ambient, Task High Pressure Sodium Ceramic Metal Halide Clear Clear (2) (2) 70 100 5350 6150 59 51 1900 22 3000, 4000 90 12,000 Exterior Area Lighting 12,000 Exterior Area Lighting (3) (3) (3) 20-100+ variable (4) LEDs 70+ Task, Accent, Colours Table 2-1 Quick Reference Lighting Source Comparisons Notes: 1. Reflector style lamps are often rated in Centre Beam Candlepower (CBCP) rather than lumens. 2. All fluorescent and HID sources require a ballast. Some are built-in and some come separately. LPW includes ballast watts. 3. LEDs operate very differently from other sources, so are difficult to compare on this basis. 4. LEDs can last <5000 hrs if heat is not controlled and >100,000 hrs if it is. 2 What Are Our Sources of Light? Size and Shape The smaller the lamp, the easier it is to fit in a small light fixture, which is often a goal from an aesthetic perspective. More importantly, it also allows the light to be aimed more accurately. An LED or halogen flashlight, for example, often has the ability to be focused in a narrow beam and can come in a small package. A compact fluorescent lantern for camping sends light in all directions and cannot be focused in such a small beam even with reflectors. Various letters are used to describe the general shape of a lamp, such as T for tubular, G for globe, and so on. The number attached to a lamp is usually the maximum diameter, measured in one eighths of an inch. A T8 lamp is a tube shape, with a diameter of 8/8 in. (1 in.). An MR16, which is the most common reflector lamp used in track and many recessed fixtures, is a Multifaceted Reflector lamp with a diameter of 16/8 in. (2 in.). 21 Figure 2-2 From miniature xenon lamps to compact fluorescent screw-in lamps, all have their place and application. Courtesy: Ushio, TCP Cost Lamps can range from under $1 for a typical 60W incandescent bulb to over $300 for a specialty lamp used in fibre optic lighting or LCD (liquid crystal display) projectors. The real cost, however, is the energy consumed. For example, the 60W bulb could cost approximately $15.00 to operate depending on its rated life. Thus a compact fluorescent lamp could actually be quite inexpensive in comparison, costing less than $5 to operate over that same period. Colour Temperature (CCT) and Colour Rendering (CRI) These topics were covered in Section 1 and are important factors when choosing a source. Most homeowners are more comfortable with a warm source (2700° K -- 3000° K), with the highest CRI available (>80) for that particular source. Transformers and Ballasts Some lamps require a transformer to take household voltage of 120V down to 12V (most popular halogen lamps run at 12V). These transformers are usually about the size of a deck of cards and can be magnetic or electronic. Most often, these are attached to each fixture. In some cases, a larger transformer can be used to feed an entire track system with multiple light fixtures. 2 What Are Our Sources of Light? Ballasts are used in fluorescent and other arc-type lamps to help strike the initial arc since there is no filament to conduct the electricity. They help to control the electricity during operation. Screw-in compact fluorescent lamps contain the ballast right in the base, whereas 4-foot long tubes require a ballast within the fixture for operation. Figure 2-3 Electronic ballasts and transformers are recommended to eliminate lamp flicker, reduce audible hum and improve efficiency. Courtesy: Philips Lighting b. What are the lamp categories? A variety of lamp types are available but, for residential applications, the most common are incandescent (standard and halogen) and fluorescent, with LEDs beginning to make in-roads. Standard Incandescent 22 The most common source used in our homes today is the standard incandescent lamp -- particularly the familiar 60W screw-in bulb. It was invented by Thomas Edison over 100 years ago and is often described as a ‘‘hot wire in a bottle’’, with the hot wire being a tungsten filament. Standard incandescent lamps are the most inefficient source available and should be used sparingly. The Federal Government has introduced legislation to ban the standard incandescent lamp by 2012. (See Appendix ll for details) Figure 2-4 Over 90% of the energy used by a standard incandescent lamp is wasted as heat, leaving less than 10% emitted as visible light. 2 What Are Our Sources of Light? Figure 2-5 Above is the typical construction of an incandescent lamp. Below, the general shapes and designations of incandescent lamps. Courtesy: CEATI Lighting Reference Guide 7015 23 Halogen Incandescent A halogen incandescent encloses the tungsten filament in a small quartz capsule (thus the commonly used terms quartz halogen), which contains halogen gases. This construction allows the filament to get slightly hotter than standard incandescent, which means some of the cooler (bluish) colours are produced and an overall whiter light is produced (2900° K vs 2700° K). In addition, the halogen gases used help to make the filament last longer, usually in the 2000 hour range rather than the 1000 hour range for standard incandescent. Halogen incandescent is also 10% -- 20% more efficient than standard incandescent. Figure 2-6 Halogen is a slightly more efficient incandescent source that also lasts longer and is somewhat whiter in appearance. Courtesy: OSRAM Sylvania 2 What Are Our Sources of Light? Figure 2-7 Common halogen shapes. The general shapes apply to both standard and halogen incandescent lamps. Halogen lamps are typically more tubular or reflector shaped. Courtesy: CEATI Lighting Reference Guide 7015 Low voltage (12v) halogen uses the same construction as described. However, the lower voltage allows a smaller filament to be used, which means all the light is emitted from a smaller location and can be aimed and focused more accurately. For example, this is evident in the MR16 style lamps, where a wide variety of beamspreads can be purchased (from narrow spot to wide flood). 24 Figure 2-8 120V Halogen reflector lamps come in a variety of sizes and wattages. Courtesy: Philips Lighting Figure 2-9 Reflector lamps with frosted lenses soften the beam pattern. A wide variety of beam spreads, reflector types and rated life is available. Courtesy: Ushio 2 What Are Our Sources of Light? Halogen Benefits • • • • • • • Small, easily aimed More efficient than standard incandescent (10 -- 20%) Variety of shapes and sizes Easily dimmed High CRI (100 by definition) and warm colour Relatively low cost No ballast required Halogen Disadvantages • • • • • Light yellows when dimmed for all incandescent lamps Must run at full output occasionally to maintain lamp life Very hot to the touch, care must be taken to keep flammable materials away Touching the quartz tube enclosing the filament can reduce lamp life 3 to 4 times less efficient compared to fluorescent Halogen reflector lamps come in a variety of beam spreads. A spot distribution from an AR111 halogen lamp can have a beam spread of 4 degrees, allowing it to accent a piece of art from across the room! On the other hand, a wide flood beam spread from an MR16 lamp can light up an entire picture from just a few feet away. 25 Figure 2-10 For a typical home, consider using a beam spread of about 35 degrees (called flood or FL) for most halogen reflector lamps. Fluorescent: Fluorescent lamps were introduced to the commercial market in the mid-1900s, with the common ‘Cool White’ and ‘Warm White’ colour temperatures, usually in 4-foot lengths. They were relatively energy efficient, however they produced a poor quality light that washed out many colours. They required a ballast to properly start and run the lamps, which created a flicker noticeable to many and often produced an audible hum. 2 What Are Our Sources of Light? Figure 2-11 Common fluorescent lamp shapes. Courtesy: CEATI Lighting Reference Guide 7015 26 Figure 2-12 Two, 3 and 4-foot T8 lamps provide excellent Colour Rendering (~85) and a variety of Colour Temperature options (~3000°K is recommended for homes). In the early 1990s, 4-foot T8 fluorescent lamps were introduced, using tri-phosphor coatings (red, green and blue) to produce a better colour quality and a wider variety of colour temperatures. Soon after, electronic ballasts were introduced, which improved efficiency even further, eliminated lamp flicker and operated more quietly. Compact fluorescent lamps (CFL) have followed behind their full-sized cousins. Today, electronic ballasts, good colour rendering and warm colour temperatures are available to provide a reasonable replacement for many standard incandescent and halogen sources. They cannot be focused particularly well, but are suitable for ambient light applications, including recessed downlights. Most CFLs will take a minute or two to come to full brightness. 2 What Are Our Sources of Light? Figure 2-13 Before buying a large number of compact fluorescent sources for your home, try a few from different manufacturers and see which you prefer in terms of colour, warm-up time, and fit within the fixture. Courtesy: Philips Lighting, TCP Various CFL sources should be tested in multiple locations to see which combination of manufacturer, colour temperature and colour rendering best bring out the colours as desired. Fluorescent Benefits • • • • • • Extremely energy efficient, 3 to 4 times halogen Long life (10,000 hours CFL to 20,000+ hours full size) CRI of 80 to 90 available (avoid CFLs <80 CRI) Excellent for ambient lighting Cool to the touch Variety of shapes and sizes for many applications Fluorescent Disadvantages • • • • • Higher cost fixtures initially Not readily dimmable (although dimming ballasts are available) CFLs take a minute or two to come to full output Sensitive to heat and cold While colour quality is very good, there can be noticeable differences in colour appearance when compared to halogen sources. This is not necessarily bad, just different. High Intensity Discharge High Pressure Sodium (HPS) and Metal Halide (MH) sources are not used in homes since they can take as long as 10 minutes to come to full output. However, unlike fluorescent, they are not affected by cold temperatures and can be applicable for area lighting on acreages and farms. They are approximately as efficient as fluorescent and require a ballast for starting and running. HPS sources are used for street lighting and provide a yellow-orange light with a very low CRI of 22. However they are more efficient and last longer than MH. MH provides a whiter light, which is often more desirable. A Pulse Start Metal Halide source improves upon the original MH technology and should be used if applicable. 27 2 What Are Our Sources of Light? Figure 2-14 High Intensity Discharge (HID) sources are suitable for exterior area lighting on acreages and farms. Courtesy: OSRAM Sylvania HID Benefits • • • Long life (15,000+ hours depending on wattage) Extremely energy efficient Not susceptible to cold, good for acreages and farms for area security HID Disadvantages • • 28 Long warm up time (5 to 10 minutes) HPS has very poor colour quality (22 CRI) Light Emitting Diode (LED) LEDs are electronic devices, mounted on micro-chips with no filament or parts to burn out. They were introduced as indicator lights in the 1960s, showing up in early calculators as well. These early LEDs were typically less than 0.1W, not required to produce any significant lumens and only available in warmer (red, orange, yellow) colours. In the mid 1990s, the invention of the blue LED started a revolution in the lighting industry. By adding blue to the existing red and green LEDs, white light could be produced. More recently, it was discovered that using blue/ultraviolet LEDs with a phosphor-coated lens, similar to the fluorescent lamp, produced the best white light. Figure 2-15 LEDs have more in common with your computer than they do with a typical lamp. Courtesy: CREE LED Lighting Solutions 2 What Are Our Sources of Light? LED Myths As wattages increased and white light LEDs became viable sources for commercial and residential use, two myths developed. First, that they produced ‘no heat’ and second that they never burned out. In fact, high power (>1W) LEDs produce plenty of heat but, rather than in the form of Infrared (IR) heat that is radiated away from halogen lamps, an LED produces heat at the back of the chip, which must be conducted away by fins or other cooling methods. This need for cooling is identical to that required in computers and, like computers, if the heat is allowed to build up both computer chips and LEDs will fail. This leads to myth #2. While LEDs can last for decades in theory, in reality the ability to keep the LED cool determines its actual life as well as its depreciation rate. Figure 2-16 Heating fins highlight the critical need to remove heat from high output LEDs during operation. Courtesy: CRS Electronics, CREE LED Lighting Solutions Over the past 25 years, we have seen the computer industry grow at an incredible rate, leading to a revolution in the way we work, communicate and even think. We are now witnessing the start of similar growth in the LED lighting industry. Almost monthly, higher wattages and improved efficacy milestones are being reached. Eventually, LEDs will be superior to all other sources in efficiency, size and controllability. However, there are significant obstacles. Successful fixture manufacturers are rethinking fixture design from the ground up in order to harness the benefits of LEDs. LED Benefits • • • • • Potentially extremely long life (100,000 hours +) Potentially applicable for all lighting needs Potentially extremely energy efficient (beyond fluorescent) Wide variety of colours available now for decorative purposes Can produce colours much more efficiently than filtering other sources LED Disadvantages • • • • Expensive fixtures and lamps, usually not sold separately Lack of industry standards makes quality control a major concern Fast-changing technology makes products obsolete in a matter of months Heat build-up drastically shortens life and reduces light output 29 2 What Are Our Sources of Light? Figure 2-17 LEDs are extremely good at efficiently producing colours. They are also becoming more common and effective in smaller decorative fixtures and in task applications such as step-lights and under-cabinet fixtures. Courtesy: OSRAM Sylvania, Magic Lite, Progress Lighting; GVA Lighting 30 Now that we have a good overview of the various light sources available, we’re ready to look at lighting fixtures and their applications in the following sections. 3 What Are the Options for Light Fixtures? 3 WHAT ARE THE OPTIONS FOR LIGHT FIXTURES? Light fixtures allow us to control glare, put light where we want it, provide a place for ballasts and transformers and, maybe most importantly, provide attractive aesthetics. In the lighting industry, light fixtures are correctly called luminaires, with the term fixture typically reserved for plumbing products. However, we will use the terms ‘fixture’ and ‘light fixture’ since they are so widely used and understood. A brief look through the websites of firms that have graciously provided pictures for this publication will reveal literally thousands of available fixtures. Popular styles alone include traditional, transitional, country, folk, casual, Victorian, tiffany, art deco, art nouveau, mission, utility, Spanish, eclectic and so forth. Add to this a wide choice of colours, finishes, locations and types, and the selection is truly overwhelming. It is useful however to sort fixtures into the general type categories of surface, pendant, recessed, track, portable, landscape and fibre optic. These are often broken down further into semi versions, such as semirecessed. a. Surface Surface As the name implies, surface mounted fixtures are exposed but remain close to or flush with the ceiling or wall. Surface mounted fixtures provide clearance for walking under, so are popular in hallways and bedrooms. Most utility and under-cabinet fixtures are also surface. A sconce is a surface mounted fixture mounted on a wall and can be used above bathroom mirrors, exterior entry ways and garages and for decorative purposes in other locations. 31 Figure 3-1 A sample of surface fixtures available. Courtesy: (left to right) Magic Lite (2), Nuvo Lighting (2), Juno Lighting, Kichler Lighting, and World Imports (2). 3 What Are the Options for Light Fixtures? b. Pendant Fixtures that are suspended by cord, chain, cable or other means are referred to as pendant. Pendants are popular over tables, kitchen islands and in higher ceiling areas, as their height above the floor typically doesn’t allow one to walk underneath. Pendant fixtures have the benefit of being able to direct light upwards, downwards, or both. This allows them to provide both soft ambient light reflected from the ceiling, as well as directional task light directed towards a table, for example. In some cases they contain aimable heads similar to track lighting systems. 32 Figure 3-2 A sample of pendant lights available. Courtesy: (left to right) Juno Lighting, Satco Lighting, Jesco Lighting, Progress Lighting, Kichler Lighting, World Imports and Cooper Lighting c. Recessed Recessed lighting, usually in the form of downlights (or potlights), is typically found within a ceiling cavity. In some cases, decorative trims are added below the ceiling line, so are considered semi-recessed. Some recessed lighting can be found in vertical surfaces, such as stair lights. While round is the most common shape, square recessed fixtures provide an interesting aesthetic. Most of the fixture is typically hidden, so a wide variety of surface trims is available. Recessed lighting can be used in virtually every room in the home, however it should not be forced to provide all the layers required in an effective design. 3 What Are the Options for Light Fixtures? Figure 3-3 A sample of recessed light fixtures available. Courtesy (left to right) Cooper Lighting (2), Magic Lite, Oligo Lighting (2), GVA Lighting and Juno Lighting (2). d. Track The need for flexibility in location, quantity, aiming angles and style of fixtures led to the popularity of track lighting. Track lighting has become much more sophisticated in function and appearance, with multiple circuits and voltages, finishes, colours and styles. Track can also be surface mounted on walls or ceilings, or suspended. The fixtures themselves come in a variety of shapes, sizes and styles installed on a single section, including pendants. Track lighting works especially well in kitchens. Later additions to the track family have included cable lighting, where the conductors are stretched between two points and become the mounting points for the fixtures, curved track, which provides true flexibility, and rail track, similar to cables but using solid conductors. Figure 3-4 A sample of the track lighting fixtures available. Courtesy: (left to right) Cooper Lighting (3), Juno Lighting (3) and Oligo Lighting (2). 33 3 What Are the Options for Light Fixtures? e. Portable Portable fixtures are typically defined by their cord, which can be plugged in wherever an electrical outlet is available. Desk and bed lights, pole lights, torchieres and some picture lights fall into this category. Portable lights can complement furniture, help fill in dark spots and are often more flexible than track lighting. Look for opportunities to add fluorescent portable lighting to provide energy efficient ambient light in bedrooms and living rooms. 34 Figure 3-5 A sample of portable fixtures available. Courtesy: (left to right) Lighting Solutions (2), TCP (2), Jesco Lighting and Magic Lite. f. Landscape This term generally refers to outdoor-rated fixtures, used to accent trees, walkways, flower-gardens and often includes deck lighting. Most landscape lighting should be 12V, providing safety and ease of wiring. This does, however, limit the number of fixtures per wire to about 150W total for #12 gauge wire, so multiple wires may be needed from the transformer. Figure 3-6 A sample of landscape light fixtures available. Courtesy: Kichler Lighting 3 What Are the Options for Light Fixtures? g. Fibre Optic Some of us are familiar with the older fibre optic lamps that provided thin, clear fibres, which emitted colourchanging light out the ends. These same principles are used in modern fibre optic illuminators, fibre and fixture systems. A fibre optic system allows for safe, functional and decorative light in pools, saunas and other areas where moisture or other limitations make it desirable to keep the electric source well away from the actual point where light is used. The fibres carry only light, no electricity, so are completely safe in any location. Figure 3-7 A sample of fibre optic lamps available. Courtesy: Magic Lite h. Daylighting In the commercial world, the practice of daylighting considers the sun and sky as sources and various windows, tubes and other entry points into the interior world as a type of light fixture. In residential applications, the most common approaches to bringing extra daylight into a space are skylights and light tubes. Figure 3-8 Skylights and light tubes are the most common residential forms of skylighting. Courtesy: Sunscope 35 3 What Are the Options for Light Fixtures? i. Accessories Most fixtures allow the addition of filters, shields, shades and other methods to direct or otherwise control the light as required. These accessories are often under-utilized and can soften glare and provide interesting and attractive aesthetics. Honeycomb louvers can be placed in front of an MR16 lamp to eliminate the glare common with these widely-used sources. Figure 3-9 Light fixture accessories can direct or control light as required. Courtesy: Cooper Lighting j. 36 Efficiency We have talked about efficacy, the number of lumens per watt (LPW) produced by a source. The term efficiency is applied to fixtures and is a measure of how much light escapes the fixture vs. how much light is produced by the source. For example, if a bare compact fluorescent source provides 1000 lumens, but when installed in a fixture only 600 lumens escape, the fixture is 60% efficient. In many cases, a fixture is chosen simply because it looks attractive. However, if it is very inefficient or does not direct the light where it is required, it is a poor choice. Energy cost of light fixtures It is worth learning how to calculate the cost of lighting in order to compare various options economically. We need to know three things to do this: • • • Power of the source in kilo-Watts (kW) Time the source operates in hours (h) Utility rate in ¢ per kWh (This should include all variable costs you are charged) Let’s use a 60W lamp as a simple example. If three of these are used in a pendant fixture in the front hall and burn four hours each evening, how much does it cost in a year for electricity assuming an electricity rate of 10¢ per kWh? Total Power in Watts = 3 x 60W = 180W Total Power in kilo-Watts = 180W÷1000 = 0.180kW Total time per year = 4 hr per day x 365 days per year = 1460hr Total electricity consumed = 0.180 kW x 1460h = 262.8 kWh Cost per year = 262.8 kWh x 10¢ per kWh = 2628¢ (or $26.28). 3 What Are the Options for Light Fixtures? Thus, it costs over $26 to run this fixture for a year. If 15W compact fluorescent screw-in ‘spiral’ lamps are used instead, the cost would be 1/4 of this since 15W is one quarter of 60W. The yearly cost would be $26.28 ÷ 4 = $6.57, saving almost $20 per year. Table 3-1 provides a guide for replacing standard incandescent lamps with CFLs. Standard Incandescent Lamp (watts) Energy Star Qualified CFL (approximate equivalent watts) Minimum Light Output (lumens) 40 60 75 100 150 9 -13 13 - 15 18 - 25 25 - 30 30 - 52 450 800 1100 1600 2600 Table 3-1 Screw-in Compact Fluorescent Replacement Recommendations Source: NRCan/OEE There are costs to lighting our homes. A financial cost when we buy the fixtures, a monthly cost to buy the electricity to run them and, finally, an environmental cost to create the electricity we buy. It is tempting to consider only the first cost of a light fixture at a store, but a few calculations might prove that a more expensive but energy efficient light fixture or lamp is worth it in the long run. The following tables summarize the comparison of a screw-in 15W compact fluorescent spiral lamp versus the most common lamp used for decades, a screw-in 60W incandescent. Electricity Price ($/kWh) $0.06 $0.08 $0.10 $0.12 $0.14 4 6 Hours ON per day 8 10 12 $3.94 $5.26 $6.57 $7.88 $9.20 $5.91 $7.88 $9.86 $11.83 $13.80 $7.88 $10.51 $13.14 $15.77 $18.40 $9.86 $13.14 $16.43 $19.71 $23.00 $11.83 $15.77 $19.71 $23.65 $27.59 Table 3-2 How much money do I save each year by replacing one 60W incandescent lamp with one 15W compact fluorescent lamp? Payback (months) 4 6 Hours ON per day 8 10 12 9.1 6.8 5.5 4.6 3.9 6.1 4.6 3.7 3.0 2.6 4.6 3.4 2.7 2.3 2.0 3.7 2.7 2.2 1.8 1.6 3.0 2.3 1.8 1.5 1.3 Table 3-3 How long does it take to get my money back by replacing a 60W incandescent lamp with one 15W compact fluorescent lamp? Based on $1.00 for one 60W incandescent lamp and $4.00 for one 15W CFL cost. Electricity Price ($/kWh) $0.06 $0.08 $0.10 $0.12 $0.14 60W Incandescent 15WCFL $36.80 $46.40 $56.00 $65.60 $75.20 $11.20 $13.60 $16.00 $18.40 $20.80 Table 3-4 How much does it cost me for both lamps and electricity over the 8000 hours that my 15W compact fluorescent lamp will last (assuming a lifetime of 1000 hours for an incandescent bulb)? 37 3 What Are the Options for Light Fixtures? k. Fixture selection criteria While the types of fixtures can be overwhelming, the next two sections will discuss some practical design concepts (Section 4) and how to pull everything together for a home lighting design (Section 5). However, some general comments and specific concerns about fixture selection are in order before we get into the ‘fun’ stuff. Heat build-up with Compact Fluorescent Lamps (CFL) Lamps produce heat, the more inefficient, the more heat is produced. Choosing energy efficient sources and fixtures helps reduce this waste heat. It is important to manage any heat so it doesn’t cause a fire hazard or damage the light fixture or associated electronics. The following tips will help control these heat problems: • • • • Choose downlights (potlights) that use a built-in ballast, located on the frame, and a plug-in lamp. This helps keeps the heat away from the actual lamp. Make sure the fixtures use electronic ballasts, which run cooler, more quietly and without flicker When changing existing incandescent or halogen downlight lamps to CFL, avoid the common spiral options and use a CFL with a reflector made specifically for downlights. Use the lowest wattage that accomplishes the desired light level. Choose surface-mounted fixtures that are not fully enclosed. For example, frosted dishes leave a gap for air to circulate past the lamps. 38 Figure 3-10 Choose fixtures that allow heat to escape out the top when using CFL lamps. Courtesy: Kichler Lighting Fixture quality, performance and cost Our home is typically our most valuable possession. It’s where we spend a significant amount of time, particularly in the evenings when electric lighting is required. Some homeowners spend thousands on a granite countertop, rock fireplace, jet-tub or artwork. But when it comes to lighting these features and rooms well, we often choose poor quality products. With lighting fixtures, as with all products, it is worth buying quality. Poor quality fixtures won’t perform or last and the extra time it takes to research and purchase a good quality option will ultimately make your home more enjoyable, attractive, efficient, headache-free, safe and valuable. A visit to a lighting showroom and a conversation with a lighting specialist who has at least a couple years’ experience will pay dividends. The investment in good quality lighting for an entire home is usually minor compared to the cost of renovating a kitchen or bathroom. You’ll be glad you did. 3 What Are the Options for Light Fixtures? Figure 3-11 This ‘inexpensive’ fixture could hardly be considered stylish and the opal coloured lens absorbs about 60% of the light produced by the lamps. Frosted or prismatic lenses generally allow over 80% of the light to pass through. Coloured or opal lenses can absorb 50% or more, which is an inefficient choice. Safety The Canadian Building Code requires recessed downlights in insulated ceilings to be IC rated (Insulated Contact), providing a non-combustible barrier and breathing space between the insulation and the source to avoid excess heat build-up. During renovations, it’s critical from a safety and insurance point of view that current building codes are met. All light fixtures must legally have a CSA or cUL label affixed, which means it has met certain safety standards. 39 Figure 3-12 A wide variety of CFL torchieres and pole lights are now available, which are much safer and more energy efficient. Courtesy: TCP Halogen torchieres (typically 300W halogen indirect pole lamps) were a popular method of creating ambient light in living rooms. Because they are terribly inefficient (and therefore extremely hot!), they create a safety hazard when they are tipped over or come into contact with combustible materials such as curtains or paper airplanes. Compact fluorescent options are now available that are reasonably priced and provide a much safer, more efficient option. Energy efficient fluorescent & LED sources = less heat = safer & less expensive operation! Lenses Avoid the commonly used ‘opal’ lens, which absorb as much as 50% of the light as it passes through. These were often used in place of prismatic lenses, which are commercial in appearance and not as attractive. Now, there are frosted versions available that combine better aesthetics with higher efficiency. 3 What Are the Options for Light Fixtures? Figure 3-13 Frosted lenses allow more light to pass through than white or opal lenses. Courtesy: World Imports Glare control During normal activities in a home the source should either be hidden or diffused to minimize glare. The following concepts will help achieve this; • • • • Lamps within recessed downlights should either be located well up into the reflector to cut off the view of the lamp or should be aimed toward art or other objects to be accented. Choose fixtures that direct light toward ceilings and walls, using reflection to create a soft, open and diffuse ambient light. Use the lowest wattage that will do the job effectively. Don’t force decorative fixtures to provide too much ambient light. 40 Figure 3-14 Recess lamps into downlights so they are not directly visible while walking by. 3 What Are the Options for Light Fixtures? Renovations Surface mounted fixtures can be replaced and, with some rewiring, can even be moved during renovations. However, unless all the drywall is removed, access to ceiling spaces can be difficult or impossible, depending on attic access. A few ideas to keep in mind include: • • • • If required, employ an electrician with renovation experience and check references. Recessed downlights are available that can be inserted from below through the trim hole, even with an IC rating for insulated ceilings. Holes for wiring can be drilled via extension bits from hole to hole so an entire bedroom, for example, can be done with new recessed downlights without having to remove drywall or gain attic access. Install new dimmers and switches if the lighting system is upgraded, particularly if using electronic ballasts and/or transformers. Make sure an electrical permit is taken out for the work to ensure all codes are met and insurance coverage can be maintained. 41 Figure 3-15 Remodel downlights are available that can be inserted into the ceiling from below. If insulation is present, IC remodel housings are available, though not as common. Courtesy: Cooper Lighting l. Exterior considerations In much of North America, we experience a four season environment with dramatic differences in temperature and moisture from season to season - sometimes from hour to hour! During the winter, a fixture will heat up when turned on, melting the accumulated ice or snow. If the resulting water collects, it can be ‘sucked’ into a sealed fixture even through a pinhole as it cools down and then a vacuum forms. On the other hand, poorly sealed or non-sealed fixtures will allow bugs, dirt and dust to accumulate on lenses. Some things to keep in mind when choosing an exterior fixture include: • • • • • They must be listed for Wet Location The style and colour should match the home’s architecture and colour. Consider using a compact fluorescent source----they can work well even in cold environments. Use an enclosed fixture to retain some of the heat and a CFL lamp that is rated for cold environments. Consider using a timer instead of a standard switch. Some can be programmed so they turn on at dusk (latitude is programmed in) and off at midnight. If using a halogen source, consider installing an exterior occupancy sensor so the lights only come on if people are in the vicinity. From a safety and security point of view, this approach has the added benefit of providing a visible notification when someone is close by. 3 What Are the Options for Light Fixtures? • • Choose a fixture and location, which when combined, limits the amount of wasted light directed upwards into the sky. Not only is this inefficient but also adds to light pollution----the haze around most big cities that clouds our view of the stars. Be careful not to direct light into neighbours’ yards or windows, known as light trespass. Figure 3-16 Use an enclosed CFL rated for cold in exterior fixtures. Courtesy: Philips Lighting 42 Figure 3-17 Consider using ‘night sky friendly’ fixtures that only allow light to escape downwards. Courtesy: World Imports As we mentioned at the outset, lighting can be both effective and efficient. Effective so it can evoke a mood, light a task or provide security. Efficient so we can get the effects we want but still be mindful of our energy use. Effective and efficient residential lighting requires a mix of artistic and scientific skills. Now that we know the pros and cons of the various light fixtures and are getting a sense of the selection criteria, we’ve got a lot of the science behind us. We’re ready to move on to the actual design principles, where we can exercise our artistic abilities. 4 What Are the Principles Behind Good Lighting Design? 4 WHAT ARE THE PRINCIPLES BEHIND GOOD LIGHTING DESIGN? Given all the variables we have discussed in the preceding chapters, the process of designing the lighting for a home can feel overwhelming. There are many lamps and fixtures available but little information about how and where to use them. In this chapter, we bring together the various design principles and techniques to provide a practical approach, make this task less overwhelming and let your inner creative being loose! a. Light layering Effectively lighting a live concert or theatre production requires the application of multiple layers of light, such as background colours, moving lasers or highlighting the actors or musicians. Effective residential lighting is applied in layers as well. The four primary layers of light used in lighting a home are: ambient, task, accent and decorative. Ambient Ambient light is soft, diffuse light that fills a room, reduces shadows and creates a sense of openness and comfort. It is usually indirect in nature, produced by light bouncing off ceilings, walls or other architectural features. The light is diffused in all directions into the space. The best ambient lighting is produced when the source is not visible so there is no glare or dramatic contrast. Ambient light is particularly important when it comes to seeing the faces of family and friends. Since fixtures are often located in the ceiling and aimed towards the floor, it is easy to end up with shadowed faces, much like holding a flashlight over someone’s head. This effect is not flattering and can be a distraction. Since human communication includes a significant amount of non-verbal cues, such as facial movements, these cues can be lost. Figure 4-1 Directing light towards a light coloured ceiling will create diffuse ambient light, which helps fill in shadows and makes a space feel open and comfortable. In this case, light is also directed down, which may provide some task lighting for reading or may simply add to the ambient levels. Courtesy: Oligo Lighting 43 4 What Are the Principles Behind Good Lighting Design? Figure 4-2 Most relatively inexpensive pole-style fixtures can be operated with a compact fluorescent lamp, providing efficient and attractive ambient light. Courtesy: Lighting Solutions Inc An example of ambient light would be a fluorescent torchiere or pole lamp bouncing light off a ceiling. Other examples would include washing walls with recessed downlights or mounting fluorescent fixtures above kitchen cabinets. 44 The best source to use for ambient lighting is fluorescent. By its nature, it is already diffuse and yet can be directed towards walls and ceilings to be spread out further and inter-reflected. Ambient light requires a significant number of lumens to be effective, so energy efficiency is important -- also a feature of fluorescent. A compact fluorescent torchiere is a particularly flexible and effective tool. Task Task lighting, as the name implies, provides additional light to carry out a particular job. Tasks in the home include eating, reading, food preparation, using tools at a workbench or homework at a desk. Ambient light can help with the job but often we need more intense or directed light to allow safer, faster and more precise work. Figure 4-3 Task lighting can be portable, such as this make-up mirror, or fixed, such as under-cabinet counter lighting. Courtesy: Randall Whitehead, Magic Lite 4 What Are the Principles Behind Good Lighting Design? Usually, the source is aimed directly at the task, so direction and geometry become important. The light should be aimed so that glare is not a concern. For example, put a reading light over one shoulder or a desk lamp in a location where the source can’t be seen and the writing hand does not cast shadows. Another common application is under-cabinet lighting, where fixtures should be placed at the front of the cabinet, just behind a lip and aimed towards the backsplash. This reduces glare from glossy counter surfaces. Accent Accent lighting requires an understanding of where items might be placed that deserve particular attention. Directing significant quantities of light at these objects will cause them to jump out visually. By definition, something can only be accented if it is significantly brighter than the surrounding objects. Thus, if the ambient lighting is too bright, it is difficult to properly accent something. This can be overcome by controlling the various layers independently to create different moods. Using multiple layers allows various moods to be created through dimming and switching, with each layer controlled separately. Objects that are typically accented include paintings or photographs on walls, flower arrangements on a table, art pieces and, often, architectural details such as an exterior pillar at the front entry. Don’t try to accent too many objects. It is more dramatic and attractive to choose an important few locations. For larger objects, use two or more spotlights from different angles. 45 Figure 4-4 Accent art, antiques, pictures, or other items to which you wish to bring attention. Use a spotlight, such as an MR16 lamp, to provide much higher light levels on the object compared to the surrounding levels. Courtesy: Randall Whitehead, Lighting Solutions Inc Decorative Many types of fixtures are simply meant to look attractive rather than provide much useful light. A chandelier should NOT be expected to provide all the light in a dining room or entry. It is a decorative piece that should provide just enough light to be attractive. It is often desirable to make it appear that this is the source of light, when the primary source is something else, such as recessed downlights located nearby. Wall sconces and chandeliers are the two most common decorative products. However, any fixture that draws attention to itself through style, colour, shape, texture or other distinctive feature is decorative. Many fixtures can provide more than one layer so a wall sconce may look nice and also provide safe passage in a stairwell. 4 What Are the Principles Behind Good Lighting Design? Look for opportunities to use a decorative fixture more as art rather than forcing it to provide ambient and task lighting at the same time. Tips for Decorative Lighting • • • • • Furniture does not have to match room to room; the fixtures don’t have to either. Use a common colour or finish, such as brushed brass, to tie fixtures together while choosing differing styles. Shapes can also be a common theme throughout. Coordinate style and finish with door handles or faucets. Being eclectic and mixing styles demonstrates individuality. If you like it, try it! Choose a size that corresponds to the room dimensions. For example, vaulted ceilings, tall walls and large open spaces require something substantial in size. 46 Figure 4-5 Decorative lighting can be as simple as a candle on a table to small portable lamps. Many fixtures, such as kitchen pendants, provide both a decorative element and task lighting on an island. Courtesy: Lighting Solutions Inc, American Fluorescent b. Wall Washing, Silhouette and Grazing Some common techniques that supplement and enhance light layering principles are grazing, silhouette and wall washing. Wall washing As we walk around any space, our eyes are mostly facing forward, yet most ceiling mounted lighting directs light towards the floor. Wall washing puts light where we see it best -- straight ahead on the walls - and is a great method of creating soft ambient light. 4 What Are the Principles Behind Good Lighting Design? Figure 4-6 Downlights placed close to walls provide soft, low-glare ambient light by washing a light coloured diffuse surface. Courtesy: Cooper Lighting Silhouette An object, for example a dried flower arrangement in an alcove, can be silhouetted by shining light on the wall behind. This again can provide interest and drama in a space. 47 Figure 4-7 Low intensity LED lighting behind this vase , combined with accent lighting, creates an attractive focal point. If the accent lighting was removed, and the LEDs brightened, the vase would appear in silhouette, another attractive option. Courtesy: Randall Whitehead 4 What Are the Principles Behind Good Lighting Design? Figure 4-8 Grazing can be accomplished from any angle. The goal is to create shadows and, therefore drama and accent, by highlighting the texture of a surface. Courtesy: Randall Whitehead Grazing This is a method of highlighting wall texture by passing a narrow beam of light from top to bottom. In some cases, this is not desirable as it can bring out imperfections in the drywall finish. But, in the case of a brick wall or rock face, it can create shadows and drama that are quite attractive 48 c. Visual priorities When considering a lighting layout, it is a good idea to focus first on people, then architecture, then art. None is excluded, but lighting a home is primarily for people - to enhance their comfort and communication plus carry out the daily tasks of eating and working. This should not be lost in the excitement to create a dramatic scene. d. Control systems Part of the design process involves controlling the fixtures in an intuitive and appropriate way. The best way to do this is to visualize the space as you carry out day-to-day tasks. What events take place when you park in the garage and come in with groceries? Where would you like the switches to be? Which light fixtures would you like them to control? When you have company over for dinner and want to create an intimate atmosphere, which fixtures would you like to be able to dim? Switches and Dimmers Each layer of light should be on a separate switch or dimmer. For example, in the kitchen, task light under the counter, recessed downlights, pendants over the island and/or a pendant over the table should all be controlled separately. Usually dimmers are only required over tables for comfortable eating and conversation. 4 What Are the Principles Behind Good Lighting Design? Three-way switches allow control of lights from two locations, a useful approach in hallways and rooms with multiple entry points. Lights can be controlled from three or more locations using one or more 4-way switches in between two 3-way switches. Dimmers are also available in 3 and 4-way versions. Switched receptacles An effective approach to controlling portable lighting (table lamps, torchieres) can be to split an electrical receptacle into switched and non-switched halves. The non-switched half can be used for typical applications, while plugging the portable light into the switched half. In this way, a wall-mounted switch can control a portable lamp, which is usually much more convenient than trying to find a cord-mounted switch in the dark. Motion detectors The movement of heat sources (such as our body) can be detected by Passive Infrared (PIR) motion detectors. These provide convenience and energy savings and work well in locations such as garages, storage rooms and play rooms. Motion sensors are also an excellent way to control exterior fixtures, providing a visual cue when someone enters the area and discouraging trespassing, vandalism and theft. These need to be approved for wet conditions and typically come with the fixture to be controlled. 49 Figure 4-9 A motion detector can provide convenience and safety, turning on lights in rooms used when carrying groceries, for example. They also help reduce energy costs in rooms that are regularly used, such as children’s play-rooms or garages. Courtesy: Leviton Photocells In some cases, it is desirable to leave at least one light on all night for safety and aesthetic reasons. It is recommended that a compact fluorescent source rated for cold temperatures is used in this case, controlled by a photocell to turn it off during the day. Whole-house controls There are more complex control systems available, which allow for scheduling, control from one location, scene control through the touch of a single button, panic buttons at the bedside and even remote control via 4 What Are the Principles Behind Good Lighting Design? the internet or dial-up. Control systems use a variety of methods to communicate including wireless, separate control wiring and use of the existing house wiring (‘power-line carrier’) for signals. In existing homes, a wireless or power-line carrier system allows for retrofit control of the lighting system. Due to their complexity, it is important to research the various options available and talk to an experienced electrical contractor or home automation specialist to make sure the chosen system is easy to use, effective, expandable if required and provides the function desired. It would be very frustrating to invest time and money in a system only to have it detract from the enjoyment of your home through misapplication or poor quality. 50 Figure 4-10 A variety of firms offer whole-house control systems, integrating lighting, heating and cooling, security, energy management and other features. It is recommended that an experienced electrical contractor or home automation contractor be consulted for design and installation services on these types of complex projects. Courtesy: Leviton Code requirements and safety It is essential to meet all applicable codes and regulations when installing or upgrading a lighting system. All electrical devices must be approved, as indicated by a CSA or cUL stamp or sticker. Check with the local electrical provider for details regarding code, permit and inspection requirements. This is critical from a safety point of view and can impact insurance claims. Downlights or potlights are so common that it is important to know that recessed downlights located in insulated ceilings must have an IC (Insulated Contact) designation to avoid excess heat build up and fire hazard. A few manufacturers make an IC-rated downlight that can be used for remodeling, inserted through a hole from below. However, be aware that most commonly available remodel downlights are NOT IC rated. 4 What Are the Principles Behind Good Lighting Design? Design Process Checklist You now have a collection of tools (sources and fixtures) and techniques (light layering, grazing, etc.) to work with. The next chapter will apply these on a room by room basis. The process may still feel daunting, so here is a ‘checklist’ to help. On a room-by-room, space-by-space basis, answer the following questions to help think through the steps and prepare to sketch each room out. ˆ Make some basic notes for each room; o what are the colours to be used, finishes? o what furniture will be added and where? o what is the size, shape and ceiling height? o what tasks will be carried out in the room? (make a list for each room) o what vertical surfaces can be washed with light to provide softer and more diffuse overall lighting? ˆ Does the room need lighting design or is a simple utility fixture adequate? ˆ Choose decorative fixtures that blend with the colours, finishes and architecture. Sometimes there’s no other way but to purchase one and hold it up in the finished space. ˆ Add task lighting as required, refer to the list of tasks you made above. Make sure that the source does not shine directly into your eyes when working on the task. Be careful not to create reflected glare off shiny surfaces. ˆ If there are art, pictures, antiques or other objects worth accenting, add lighting in those locations. Again, visualize walking through the space and make sure you can never look directly into the source. If the feature will be permanent, choose aimable recessed lighting. If a lot of flexibility is required, consider track, rail or cable lighting. ˆ Decide how to achieve at least some ambient light in the room, which is best achieved through indirect or direct/indirect fixtures. This can be through hidden coves, above furniture or cupboards, or with portable torchieres and fixtures. ˆ Make sure each layer is controlled separately. Visualize yourself walking through the room from every entry point to ensure the controls are comfortable and convenient for day-to-day use. Is a switched floor or wall receptacle a good option for portable fixtures in this space? ˆ Choose the energy efficient lighting option. It will save you ongoing electricity costs and help to reduce greenhouse gases Once this process is completed, it is time to make up a quick sketch of each room and finalize the design. The following section offers some design suggestions to help trigger your own creativity. 51 4 What Are the Principles Behind Good Lighting Design? 52 5 What Are Some Practical Lighting Concepts for My Home? 5 WHAT ARE SOME PRACTICAL LIGHTING CONCEPTS FOR MY HOME? We have covered a great deal of information -- from lighting fundamentals and light sources to light fixtures and design principles. This section takes all that information and shows how all this theory contributes to efficient and effective lighting throughout your home and property. It provides key ideas to keep in mind, sample floor plans and pictures to help trigger ideas of your own. When designing the lighting for your home, it is helpful to think through the process room by room, using the Design Process Checklist from Section 4. a. Entry Ways and Hallways • • • • • • Seeing people’s faces is important, so avoid using only potlights, which can shadow. Provide accent lighting on art or pictures. Track lighting or aimable downlights can provide both accent and ambient wall wash. Use a decorative pendant or wall sconce near the door to create a welcoming atmosphere. Ensure access to switches from multiple locations. Use efficient sources as these lights are often on longer hours Key Halogen 35W MR16 Curved low voltage track S Figure 5-1 A sample Hallway/Entry floorplan. 3 3-way switch 53 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-2 Surface mounted dishes with CFL lamps provide an efficient and effective entry fixture. Courtesy: Lighting Solutions Inc 54 Figure 5-3 Rail or track lighting are good choices in hallways and entryways to accent art or pictures on the walls. LED lamps could be used instead of MR16 halogen lamps, providing efficient accent lighting. Try one out to see if you like the effect. Courtesy: Oligo Lighting b. Living Room • • • • • • Seeing people’s faces is important. Create flexibility through portable lighting. Provide good ambient/indirect lighting. Make sure glare is controlled for comfortable reading. Use switched receptacles to integrate fluorescent torchieres. Note that CFLs are not dimmable, so halogen should be used in some locations to create various scenes and an intimate atmosphere. 5 What Are Some Practical Lighting Concepts for My Home? Key Halogen downlight (50W - 90W) Portable fluorescent torchiere (2700K, >80 CRI) Halogen wall sconce (<50W) SD Dimmer switch S Switch 1/2 Switched receptacle Figure 5-4 A sample Living Room floorplan 55 Figure 5-5 Multiple fixture types in one room allows for flexibility. Wall sconces can provide effective ambient light if directed up. Portable lamps are always a good option for living rooms. Also consider matching wall sconces and pendants. Courtesy: Randall Whitehead, Kichler Lighting (2) 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-6 Use fluorescent recessed downlights to wash walls since the light spreads out well. Use halogen or LED recessed downlights to accent art, since a more focused beam is required. Courtesy: Canlyte 56 Figure 5-7 Linear cove lighting with fluorescent strips highlight vaulted ceilings in an energy efficient manner. Halogen downlights grazing a fireplace highlight the texture of the rock. This grazing effect requires a narrow beam, and therefore halogen. Courtesy: Juno Lighting 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-8 Washing walls with downlights fills the space with soft, comfortable ambient light. Courtesy: Cooper Lighting 57 c. • • • • • Dining Room Seeing people’s faces is important. Separate the control of multiple layers to create various moods. Don’t rely on a chandelier to provide all the light, supplement with downlights and sconces. Consider sconces with strong indirect effect. Aim downlights toward walls to create more ambient light. Provide dimming controls to enhance an intimate atmosphere and allow flexibility. This will require halogen lamps since most fluorescent lamps can’t be dimmed, however since the dining room isn’t used as often, energy efficiency is less important than atmosphere here. 5 What Are Some Practical Lighting Concepts for My Home? Key Halogen downlight (50W - 90W) Decorative pendant (should provide some indirect lighting) Halogen wall sconce (<50W) SD Dimmer switch 58 Figure 5-9 A sample Dining Room floorplan. Figure 5-10 Sometimes, simple works best with a stylish pendant over the table. Pendant fixtures with indirect light enhance attractive ceilings. Courtesy: (left to right) Jesco Lighting, Kichler Lighting, Nuvo Lighting 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-11 Cable or flexible rail lighting can provide flexibility and multiple layers within a single system. Courtesy: Oligo Lighting 59 Figure 5-12 Chandeliers are decorative and should be kept relatively dim. Supplement with downlights. Most of the light on this table is from the recessed downlights, not the chandelier. Courtesy: Juno Lighting 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-13 Portable lights can take many forms and will enhance the atmosphere of most rooms. A well-chosen fixture can be decorative while providing enough light to visit and eat comfortably. Courtesy: Randall Whitehead Kitchen d. Kitchen 60 • • • • • • Seeing people’s faces is important. Avoid track lighting in favour of multiple layers with separate controls. Control glare on reflective counters with task lights under front of cabinets. Remember that kitchens can be a gathering place for social functions. Wash light down cabinets to bring out colours and wood grains. Kitchen lights are on a lot, so energy efficient choices are particularly important! Key 26 Watt CFL recessed downlight Fluorescent under-cabinet (T8 or T5) S3 3-way switch S Switch Note: All fluorescent should be; >80 CRI 2700K Figure 5-14 Sample 1 Kitchen floorplan. 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-15 Locate at least one downlight over the sink. Courtesy: Canlyte Over-cabinet lights should be positioned near the back to wash ceilings. Under-cabinet lights should be placed towards the front to avoid glare off counter tops. This is a great place for energy efficient LED strip lights (use ‘warm white’ or 2700K) Consider rope light in the toe-kick to provide an attractive glow. Figure 5-16 Over-cabinet and under-cabinet lighting provides an attractive look and plenty of task lighting. Courtesy: (left to right) Magic Lite, Randall Whitehead 61 5 What Are Some Practical Lighting Concepts for My Home? Key 26 Watt CFL recessed downlight Decorative pendant Fluorescent under-cabinet (T8 or T5) Fluorescent above-cabinet (T8 or T5) S3 S SD 3-way switch Switch Dimmer switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-17 Sample 2 Kitchen floorplan. 62 Figure 5-18 Larger pendant fixtures can be an attractive focal point (left), while skylight, finished with a soft diffuser, brings welcome daylight into a kitchen. Using no electricity, skylights use the most efficient light source; the sun! Courtesy: Kichler Lighting, Sunscope 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-19 This kitchen is lit with 6 -5.5 Watt LED lamps (shown above), providing a more intimate and subdued kitchen. While more expensive, LEDs equal or exceed the efficiency of CFLs. Courtesy: CRS Electronics e. • • • • • Bedroom Provide glare control while reading. Create ambient light by washing walls with downlights or with surface or pendant fixtures. If using a single fixture, consider a pendant with both uplight and downlight. Put closet lights directly above the door frame. Choose efficient sources for kids’ bedrooms if they are used a lot. 63 Key 26 Watt CFL recessed downlight Fluorescent above door (T8 or T5) Halogen downlight S SD Switch Dimmer switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-20 Sample 1 Bedroom floorplan. 5 What Are Some Practical Lighting Concepts for My Home? 64 Figure 5-21 Recessed halogen downlights on dimmers allow the homeowner to set a relaxing mood. LED reading lights can be dimmed and directed as required. Closet lighting above the door highlights clothing. Courtesy: Lighting Solutions Inc 5 What Are Some Practical Lighting Concepts for My Home? Key 26 Watt CFL recessed downlight Fluorescent above door (T8 or T5) S Switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-22 Sample 2 Bedroom floorplan. 65 Figure 5-23 Shades on bedside lamps should allow some light to filter through for reading. Colours and styles can be chosen to blend in or stand out. Courtesy Kichler Lighting 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-24 Larger walk-in closets should be layered with ambient and task lighting. Courtesy: Randall Whitehead 66 Figure 5-25 One downlight in each corner of a smaller room can often create an attractive and symmetrical effect. Courtesy: Lighting Solutions Inc f. • • • • • Bathroom Strong light should be directed towards the face while standing at the mirror. Use wall-mounted sconces or decorative linear fluorescent strips. Consider a small LED light by the toilet for safe night passage without blinding light. Provide a dimmable light over the tub for reading, located over the head area. Separate fan control from lighting control. Screw-in fluorescent lamps provide efficiency while allowing stylish fixture choices. 5 What Are Some Practical Lighting Concepts for My Home? Key 26 Watt CFL recessed downlight Fluorescent wall-mount (T8 or T5) for above mirror S Switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-26 Sample 1 Bathroom floorplan. 67 Figure 5-27 Choosing attractive wall mounted fixtures is the most common method of ensuring effective lighting of faces. Halogen (50W or more) is a good choice to accentuate skin tones. Courtesy (left to right) Nuvo Lighting, American Fluourescent, Oligo Lighting 5 What Are Some Practical Lighting Concepts for My Home? Key 26 Watt CFL recessed downlight 60W Halogen wall-mount Halogen downlight 1W LED flush-mount (24 hr/day) S SD Switch Dimmer switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-28 Sample 2 Bathroom floorplan. 68 Figure 5-29 A wide variety of wall sconces and sink area fixtures is available to fit in with the décor or make a statement on their own. Courtesy Kichler Lighting 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-30 A small LED light by the toilet provides safety at night without higher intensity light that can trigger the wake cycle. Courtesy: Lighting Solutions Inc g. Family/Great Room • • • Use multiple layers to create a bright space for play and dimmable for parties or TV. Remember that CFL sources are not dimmable, so use these for good ambient lighting, and consider dimmable halogen for a few wall sconces or grazing the fireplace. Add wall sconces for visual appeal. 69 Key Halogen wall sconce (<50W) 26 Watt CFL recessed downlight SD Dimmer switch S Switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast Figure 5-31 Sample Family/Great Room floorplan. 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-32 Combining small downlights with dramatic accents creates an intimate atmosphere for parties and TV watching. Courtesy: Cooper Lighting 70 Figure 5-33 Recessed coves provide attractive accents in any room. This is a good spot for a small LED lamp over the top. Courtesy: Canlyte Figure 5-34 Rail and track systems create flexibility. Courtesy: Oligo Lighting 5 What Are Some Practical Lighting Concepts for My Home? h. Home Office • • Consider a direct/indirect fluorescent pendant for a bright but non-glare space. These are usually found through commercial fixture sources. Use a cooler lamp (3500° K is a good choice) than in the rest of the home. Key Direct/indirect suspended fluorescent. 2 - T8 or T5 lamps Halogen downlight S SD Switch Dimmer switch Note: Fluorescent should be; >80 CRI 3500K Electronic Ballast Figure 5-35 A sample Home Office floorplan. 71 Figure 5-36 Direct/Indirect suspended fixtures create a bright but low-glare space for long hours of computer or paper work, and are very energy efficient. Courtesy: Cooper Lighting i. • • Stairwells Ensure switches are easily accessible from both the top and bottom of the stairs Consider small LED or Halogen step lights for safe yet low level lighting. 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-37 Halogen step lights provide an extra level of illumination, which is important for the aging eye. Make sure to switch these off though to conserve energy. Courtesy: Magic Lite 72 Figure 5-38 An attractive and efficient method of lighting stairs is to use low wattage (1W) LEDs on the risers as shown, or along the stringer on the side. Courtesy: Magic Lite 5 What Are Some Practical Lighting Concepts for My Home? j. • • • Garage Avoid downlights, they create harsh shadows and are not good for various tasks usually carried out in the space. 4 foot, 2 lamp vapour proof fluorescent fixtures will work well even in the cold and provide excellent overall light. Locate fixtures to each side of the vehicle(s), rather than overhead. Key 4' vapour proof 2-lamp T8 surface mount Enclosed 26W CFL wall sconce (rated for Wet Locations) S Switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast 73 Figure 5-39 Sample Garage floorplan. Figure 5-40 Vapour proof fluorescent fixtures are extremely efficient, provide great working light, keep bugs out and work well in the cold. Courtesy: Cooper Lighting 5 What Are Some Practical Lighting Concepts for My Home? k. • • Laundry Room Ensure access to switches from multiple entry locations. Provide task lighting over appliances and tables. Key 26 Watt CFL recessed downlight Fluorescent under-cabinet (T8 or T5) S3 3-way switch Note: All fluorescent should be; >80 CRI 2700K Electronic Ballast 74 Figure 5-41 Sample Laundry Room floorplan. l. Exterior Deck • • • • • Don’t allow direct viewing of lamps, the eyes are particularly sensitive to glare at night. Consider fixtures with frosted glass panes, or fixtures that provide only up and down light. Ensure all fixtures are approved for wet locations. Consider low voltage (12V), low wattage (<20W) lighting under rails or on posts. Make sure stairwells are well defined. 5 What Are Some Practical Lighting Concepts for My Home? Deck/Porch Key Halogen wall sconce (<50W) S SD SD Dimmer switch Top Rail Recessed rope light (12V). Transformer enclosed under deck. Check with local inspection authority. Figure 5-42 Sample Exterior Deck floorplan. 75 Figure 5-43 Choose exterior fixtures with frosted lenses to reduce glare. Courtesy: Randall Whitehead 5 What Are Some Practical Lighting Concepts for My Home? 76 Figure 5-44 Low wattage (<20W), low voltage (12V) lighting provides safe, low glare, and attractive exterior deck lighting. Courtesy Kichler Lighting m. Landscape • • • • Use 12V landscape lighting transformers and fixtures for safety, longevity and performance. Pathway lights should be 20W incandescent, creating pools of light on the ground. Use 35W or 50W MR16 lamps (or even better LED lamps as per the kitchen) in small spotlights shining up into trees from 0.5 m to 2 m away from the trunk, the larger the tree the further away. Deciduous trees should be lit from underneath up into the branches. Non-deciduous need to be lit from a distance, directed onto the branches and needle growth. Solar powered LED path lights provide small way-finding points of light, but no significant path or tree lighting. 5 What Are Some Practical Lighting Concepts for My Home? Figure 5-45 Use pathway fixtures to light up walks and small shrubs. Aim for small pools of light distributed through the area. Use spotlights to shine up into trees for a dramatic effect, even in winter. Courtesy: Kichler Lighting Ten things to keep in mind when lighting your home 1. Energy efficient choices are now widely available which are very cost effective, reducing your utility bills and environmental impact from electricity generation. Low-cost screw-in spiral lamps are small, last 10,000 hours, are available in 2700K and >80CRI, cost $4 or less at most large suppliers, and can be put into most light fixtures. The choice has become simple! 2. All your lamp choices should be 2700° K to 3000° K to create a warm, inviting, and relaxing atmosphere. Sometimes this is called ‘warm white’ or ‘soft white’. The packaging will usually indicate 2700K. Avoid the ‘full spectrum’ or ‘daylight’ labels, they are usually very blue in appearance, and don’t look right in most homes. 3. All your lamps should be 80CRI (Colour Rendering Index) or above. All incandescent lamps meet this criteria, but it’s important to check compact fluorescent and LED sources. 4. LED options are as efficient as CFLs, although more costly, and less widely available. They are excellent choices for under-cabinets, stairs, night safety (washrooms), and can even light an entire room! 5. Try things out first! If you’re not sure about a lamp or a fixture, buy one and try it before using it everywhere. 6. All lamps and fixtures produce heat, which must be vented to avoid safety hazards and premature failure, particularly with CFLs and LEDs. Choose fixtures which are not fully enclosed, and in potlights use the smallest CFL available that will do the job. 7. Be willing to spend a bit more on quality products. We understand the benefits of good quality tools or vehicles; longevity, performance, trouble-free operation, and resale value. The same applies to lighting your home, good quality choices are more efficient, highlight the architecture, art, and people more effectively. 77 5 What Are Some Practical Lighting Concepts for My Home? 8. Ask for help! Lighting showrooms in particular can help you select decorative fixtures, and even provide layout suggestions for various rooms you are unsure about. 9. CFLs do not dim, so when you want to create a flexible, intimate atmosphere, such as the dining or living room, halogen sources are a better option. However these lamps can be in just a few potlights or wall sconces, with CFLs providing an efficient layer to use day-to-day. 10. Layer your light using the ‘accent, ambient, decorative, and task’ ideas from Section 4. Switch the layers separately, providing multiple scenes. A final idea! Figure 5-46 Small, portable plug-in spotlights are available for under $20. Armed with a CFL floodlamp, and tucked behind or on top of furniture, these become powerful tools to gently and creatively cast light onto a ceiling or wall, adding a soft and attractive glow to a room at a very low cost. In conclusion…. 78 By adding your own imagination to the principles and ideas in this guide, we are confident you will enjoy the benefits of an efficiently and effectively lit home for years to come, while minimizing your utility bills and environmental impact! Appendix A. Glossary APPENDIX A. GLOSSARY Accent Lighting Directional lighting to emphasize a particular object or draw attention to a display item. Adaptation The process by which the human eye adjusts to a change in light level. Ambient Lighting Electric and/or natural lighting throughout a space that produces uniform general illumination. Ballast An electrical device used with fluorescent or HID (high intensity discharge) lamps to supply sufficient voltage to start and operate the lamp but then to limit the current during operation. Magnetic ballasts contain copper windings on an iron core while electronic ballasts are smaller and more efficient and contain electronic components. Base or Socket The socket is the receptacle connected to the electrical supply; the base is the end of the lamp that fits into the socket. There are many types of bases used in lamps, screw bases being the most common for incandescent and HID lamps, while bipin bases are common for linear fluorescent lamps. Bayonet A style of lamp base which uses keyways instead of threads to connect the lamp to the fixture base. The lamp is locked in place by pushing it down and turning it clockwise. Beam Angle The angular dimension of the cone of light from reflectorized lamps (such as R and PAR types) encompassing the central part of the beam out to the angle where the intensity is 50% of maximum. The beam angle sometimes called "beam spread" is often part of the ordering code for the reflectorized lamps. Beam Spread A measure of the spread of light from a reflectorized light source, a special-shaped lamp with a reflective coating inside the lamp to direct the light forward. The beam spread may be very narrow (narrow spot), very wide (wide flood), or something in-between (narrow flood, for example). Bi-Pin Any base with two metal pins for electrical contact. This is the typical base for a fluorescent tube of 1 to 4 feet in length. It consists of 2 prong contacts which connect into the fixture. Medium bi-pins are used with type T8 and T-12 tubular fluorescent lamps, and miniature bi-pins are used for tubular T-5 fluorescent lamps. Compact Fluorescent Lamp (CFL): a generic name used for a whole family of small, single-ended fluorescent lamps with a folded, bridged, or spiral glass tube design and with high colour rendering (CRI > 80) and a long life (> 8,000 hours). Cornice Lighting A built-in lighting system comprised of light sources shielded by a panel parallel to the wall and attached to the wall and distributing light on the wall and/or ceiling. 79 Appendix A. Glossary Cove Lighting A lighting system comprised of light sources shielded by a ledge or recess, and distributing light over the ceiling and possibly the upper part of the wall. Cable Lighting System A low voltage lighting system where the mechanism holding the light fixtures and conducting electricity to those fixtures is a pair of cables. Chandelier Often the focal point of the dining room. As such it should be hung about 30 inches above the tabletop and should be at least 6 inches narrower than the table on each side. Candela (cd) The measure of luminous intensity of a source in a given direction. The term has been retained from the early days of lighting when a standard candle of a fixed size and composition was defined as producing one candela in every direction. A plot of intensity versus direction is called a candela distribution curve and is often provided for reflectorized lamps and for luminaires with a lamp operating in them. Colour Rendering Index (CRI) An international system used to rate a lamp's ability to render object colours. The higher the CRI (based upon a 0-100 scale) the richer colours generally appear. CRI ratings of various lamps may be compared, but a numerical comparison is only valid if the lamps are similar in colour temperature. 80 Colour Temperature A measure of the colour appearance of a light source which helps describe the apparent "warmth" (reddish) or "coolness" (bluish) of that light source. Generally, light sources below 3200K are considered "warm;" while those above 4000K are considered "cool" light sources. The colour temperature of a lamp has nothing to do with how hot the lamp will get or how much heat is given off by the lamp. The letter, K, stands for Kelvin. Cool White A term loosely used to denote a colour temperature of around 4100 K. The Cool White (CW) designation is used specifically for T12 and other fluorescent lamps using halophosphors and having a CRI of 62. Daylight Lamp A lamp resembling the colour temperature of daylight, typically with a colour temperature of 5500 K to 6500K (note daylight lamps are not necessarily good colour rendering lamps) Dimmer, Dimming Control A device used to change the light output of a source, usually by adjusting the wattage it is being operated at. Dimming controls are increasing in popularity as energy conserving devices. The use of dimmers with incandescent, xenon, and halogen light sources also increases the life of the lamps and decreases the use of electrical energy. Downlight A small light fixture recessed into the ceiling that usually concentrates the light in a downward direction, also known as recessed down-light. Efficacy A measurement of how effective the light source is in converting electrical energy to lumens of visible light. Efficacy is measured in lumens per watt. A 100-watt light source producing 1750 lumens of light has an efficacy (efficiency) of 17.5 lumens per watt (L/W). Appendix A. Glossary Efficiency The efficiency of a light source is simply the fraction of electrical energy converted to light, i.e. energy input in watts vs. the output in lumens. It is measure in lumens per watt (LPW). Electromagnetic Spectrum A continuum of electric and magnetic radiation that can be characterized by wavelength or frequency. Visible light encompasses a small part of the electromagnetic spectrum in the region from about 380 nanometers (violet) to 770 nanometers (red) by wavelength. Filament A metal tungsten wire that incandesces or lights up when an electric current runs through it. Flexible Track Lighting System A low voltage or a line voltage lighting system consisting of a suspended electrical track where individual lighting fixtures can be mounted and moved without tools. Flicker The periodic variation in light level caused by household electrical current that can lead to strobe effects. Floodlight A luminaire used to light a scene or object to a level much brighter than its surroundings. Usually floodlights can be aimed at the object or area of interest. Fluorescent Lamp A low-pressure mercury electric-discharge lamp in which a phosphor coating on the inside of the glass tubing transforms some of the ultraviolet energy created inside the lamp into visible light. Foot Candles A unit of illuminance or light falling onto a surface. It stands for the light level on a surface one foot from a standard candle. One footcandle is equal to one lumen per square foot. The commonly United States unit of measurement of lighting level (illumination) is the foot-candle (fc). The international unit of measurement of lighting level (Illumination) is the lux (lx). The relationship between the lux and the foot-candle is 1 fc = 10.76 lux. Four-Way Switch A wall switch that allows three switches to control one lighting system. Whenever you flip one of the four-way switches in a given circuit, the light changes its state; that is, if the light was on, it then turns off and if the light was off, it then turns on. Full Spectrum Lighting A marketing term, typically associated with light sources that are similar to some forms of natural daylight (5000K and above, 90+ CRI), but sometimes more broadly used for lamps that have a smooth and continuous colour spectrum. Glare Direct glare is caused by light coming directly to the eye from a light source. Indirect glare is light reflected from a surface in the direction of the eye. Both can harm vision and cause visual discomfort or disability. 81 Appendix A. Glossary Halogen Lamp A halogen lamp is an incandescent lamp with a filament that is surrounded by halogen gases, such as iodine, chlorine, fluorine or bromine. Halogen gases allow the filaments to be operated at higher temperatures and higher efficacies. The glass envelope that surrounds the filament of a halogen lamp should not be touched with bare hands. The natural oil from human hands will shorten the life of halogen lamps. If you should accidentally touch the glass lamp, you should thoroughly remove your fingerprints with methylated spirit (denatured alcohol). Hard Wired Technically this means that the light fixture is permanently connected to an electrical source. The light fixture is not hard-wired if it gets power via a cord & plug. Illuminance The density of light (lumens/area) incident on a surface; i.e. the light level on a surface. Illuminance is measured in footcandles or lux. Incandescent Lamp A light source that generates light utilizing a thin filament wire (usually of tungsten) heated to white heat by an electric current passing through it. Indirect Lighting The method of lighting a space by directing the light from luminaires upwards towards the ceiling. The light scattered off the ceiling produces a soft, diffuse illumination for the entire area. 82 Kelvin o A unit of temperature starting from absolute zero, parallel to the Celsius (or Centigrade) scale. 0 C is 273K. Kilowatt (kW) The measure of electrical power equal to 1000 watts. Kilowatt Hour (kWh) The standard measure of electrical energy and the typical billing unit used by electrical utilities for electricity use. A 100-watt lamp operated for 10 hours consumes 1000 watt-hours (100 x 10) or one kilowatt-hour. If the utility charges $.10/kWh, then the electricity cost for the 10 hours of operation would be 10 cents (1 x $.10) Lamp A manufactured light source, synonymous with ‘light bulb’. A light source such as an incandescent, halogen, or fluorescent lamp. A lamp is sometimes called a ‘‘light lamp’’. Lamp Lumen Depreciation (LLD) The decrease over time of lamp lumen output, caused by lamp wall blackening, phosphor exhaustion, filament depreciation and other factors. LLD is listed in lamp specifications in percent at 40% of the rated life of the lamp. Lamp Size and designation Lamp shape and size are defined by a combination letter (A, S, T, etc) and a number (diameter of the lamp expressed in eighths of an inch). For Compact Fluorescent products, "S", "D", "T", and "Q" are used to represent Single, Double, Triple and Quad sizes. The code also includes a reference such as T4 to represent the size of the tube. Appendix A. Glossary Layers of Light: Layers of light in a given space are created by introducing task lighting (lighting by which people perform tasks), accent lighting (lighting used to highlight specific objects), decorative lighting (lighting created by very attractive light sources), and general lighting (lighting that fills the space). Lens A transparent or semi-transparent element which controls the distribution of light by redirecting individual rays. Luminaires often have lenses in addition to reflectors. LED (light emitting diode) A small electronic solid state device that provides light directly when electricity is passed through it. LEDs are quite energy-efficient and have very long lives. They can be red, green, blue or white in colour. Light Radiant energy that can be sensed or seen by the human eye. Visible light is measured in lumens. Light Fixture A complete lighting unit, more correctly referred to as a Luminaire, consisting of a lamp (light lamp) or lamps, a housing, and a connection to the source of electrical power. Light Loss Factor (LLF) The product of all factors, which contribute to lowering the illumination level (over time) including reflector degradation, dirt, lamp depreciation over time, voltage fluctuations, etc. Light Pollution Light that is directed to areas where it is not needed, and thereby interferes with some visual act. Light pollution directed or reflected into the sky creates a "dome" of wasted light and makes it difficult to see stars above cities. Light Trespass (Spill Light) Light that is not aimed properly or shielded effectively can spill out at into areas that don't want it: it can be directed towards drivers, pedestrians or neighbours. It is distracting and annoying and can sometimes be disabling. Louver A type of ‘‘screen’’ made of translucent or opaque material and geometrically designed to prevent lamps from being viewed directly within a given angle. Louvers are intended to minimize direct or indirect glare. Lumens A measure of the luminous flux or quantity of light emitted by a source. For example, a dinner candle provides about 12 lumens. A 60-watt Soft White incandescent lamp provides about 840 lumens. Luminaire A complete lighting unit consisting of a lamp (or lamps), ballast (or ballasts) as required together with the parts designed to distribute the light, position and protect the lamps and connect them to the power supply. A luminaire is often referred to as a lighting fixture. Luminance A measure of "surface brightness" when an observer is looking in the direction of the surface. It is measured in candelas per square meter (or per square foot) and was formerly referred to as "photometric brightness." 83 Appendix A. Glossary Lux (lx) A unit of illuminance or light falling onto a surface. One lux is equal to one lumen per square meter. Ten lux approximately equals one footcandle. Mean Lumens The average light output of a lamp over its rated life. Based on the shape of the lumen depreciation curve, for fluorescent and metal halide lamps, mean lumens are measured at 40% of rated lamp life. For mercury, and high-pressure sodium lamps, mean lumen ratings refer to lumens at 50% of rated lamp life. Monochromatic Light Light with only one wavelength (i.e. colour) present. Mounting Height Distance from the bottom of the fixture to either the floor or work plane, depending on usage. MR-16 and MR-11 A line of low voltage compact reflector lamps used for accent and spot lighting. The 16 and 11 refer to 16 eighths of an inch diameter and 11 eighths. Opaque Opaque is a term that describes a material that does not transmit any visible light. A wooden door, aluminum foil, and bricks are all examples of opaque materials. 84 PAR Lamp PAR is an acronym for parabolic aluminized reflector. A PAR lamp, which may utilize an incandescent, halogen filament or an HID arc tube, is a precision pressed-glass reflector lamp. PAR lamps rely on both the internal reflector and prisms in the lens for control of the light beam. Pendant Pendant lighting equipped with shades or globes to avoid glare, usually are suspended from the ceiling over dinette tables, game tables, kitchen counters, or other work areas. Pendants can provide both task and general lighting. In general, pendants should be hung about 30 inches above the tabletop and be about 12 inches narrower than the table on all sides. Portable Lamp A table lamp, floor lamp, or reading lamp which can be easily moved and plugged into a receptacle; officially called a portable luminaire. Phosphor An inorganic chemical compound processed into a powder and deposited on the inner glass surface of fluorescent tubes and some mercury and metal-halide lamps. Phosphors are designed to absorb short wavelength ultraviolet radiation and to transform and emit it as visible light. Photocell A device that measures the amount of incident light present in a space, used to automatically turn a lamp on and off. Appendix A. Glossary Rated Life The rated life of a lamp signifies the time at which 50% of a large quantity of these lamps will have burned out. That means that 50% of these lamps will burn out before the rated life and 50% will burn out after the rated life. The rated life does not mean that every one of the lamps will last at least that long, and is typically based on number of on hours for each start. For example, fluorescent lamps are typically based on a 3 hour on/off cycle. Recessed Downlight A small light fixture recessed into the ceiling that usually concentrates the light in a downward direction, also known as down-light. Reflector Lamp A light source with a built-in reflecting surface. Sometimes, the term is used to refer specifically to blown lamps like the R and ER lamps; at other times, it includes all reflectorized lamps like PAR and MR. Sconce An ornamental light fixture attached to a wall, also known as a wall sconce. Scotopic Vision where the rods of the retina are exclusively responsible for seeing, typically like the light levels in the countryside on a moonless, starlit night Sky Glow Also known as "light pollution". The "haze" or "glow" that surrounds highly populated areas and reduces the ability to view the nighttime sky. Specifically, light that enters the sky from outdoor lighting systems by indirect light reflected from atmospheric particles such as fog, dust, or smog. Skylight A relatively horizontal glazed roof aperture for the admission of daylight. Specular Reflection Reflection from a smooth, shiny surface, as opposed to diffuse reflection. T-12, T-8, T-5 A designation for the diameter of a tubular lamp, such as fluorescents lamps, in eighths of an inch; T-12 is 12 eighths of an inch, or 1.5 inches; T-8 is 1 inch, and so on. Task Lighting Lighting that is specifically installed to light an area where a task is performed. Three-Way Switch A wall switch that allows two switches to control one lighting system. Transformer An electrical device that transforms the line voltage of a facility (usually 120 volts for residential settings) into the voltage that a low voltage lighting system requires (12 volts or 24 volts), such as used in some halogen lamps. Translucent A term that describes a material that transmits some visible light usually with some distortion. A frosted piece of glass, a stained glass window, and paper are all examples of translucent materials. 85 Appendix A. Glossary Transparent A term that describes a material that transmits or passes visible light through it. A typical glass window pane, the air, and clear plexiglas are all examples of transparent materials. Up-light The percentage of lamp lumens directed from a luminaire (light fixture) at or above 90 degrees. UV Radiation Not visible to the naked human eye and is generally considered to be that electromagnetic radiation which has a wavelength of less than 400 nanometers (nm) and greater than 100 nm. Valance Lighting Lighting from light sources on a wall typically above eye level, shielded by horizontal panels. The light may be upward or downward directed. Wall Grazing Grazing is a method of highlighting wall texture by passing a narrow beam of light from top to bottom. It can have a dramatic highlight and shadow effect on surfaces such as draperies, stone, and brick. Grazing creates easily distinguishable high and low levels of light on the surface. Wall Washing A lighting technique that produces a relatively smooth, even level of illumination on the wall and reduces the texture of the surface. 86 Warm White Refers to a colour temperature around 3000K, providing a yellowish-white light. Appendix B. Environmental Impacts of Lighting Energy Efficiency APPENDIX B. ENVIRONMENTAL IMPACTS OF LIGHTING ENERGY EFFICIENCY Lighting can consume up to 30% of the total electricity consumption in the home, if you don’t use electricity for space heating, air conditioning or heating your water. It is also the most obvious form of energy use in the home because you can see when electricity is being consumed. In this way, it serves as a reminder not only of what it is costing but also its impact on the environment. Fortunately, as we’ve seen in this Guide, lighting quality does not have to be sacrificed to achieve efficiency. In fact, often the opposite is true. Energy Star is a federal government endorsed symbol, which identifies products that use less energy, thus lessening the environmental impact. For example, all Energy Star qualified compact fluorescent lights (CFLs) must meet minimum light outputs if they are to be replacements for higher wattage incandescent lights. Impact on the environment from the use of electricity is measured by the amount of Greenhouse Gases (GHG) produced when generating the electricity. Since electricity is generated by many different sources, the amount of GHG produced varies by jurisdiction. Check with your local utility or provincial environment department to determine appropriate conversion factors to use to determine the impact your energy efficient lighting actions will have on the environment. Currently, the incandescent lamp is the most common lamp in homes and also the most inefficient. A study done by Natural Resources Canada (NRCan) found that the average Canadian household uses more than 26 light bulbs and more than 75% are ordinary (incandescent) light bulbs. Consequently, the federal government has initiated a strategy to set performance standards for all lighting that would phase out incandescent lamps in common applications by the year 2012. NRCan estimates that these lighting efficiency standards could help reduce GHGs in Canada by over six million tonnes per year, the equivalent of taking 1.4 million vehicles off the road. Below is a guide* for the size of CFL that you could use to replace an incandescent lamp and get the same light output, measured in lumens, at a much lower wattage. Standard Incandescent Lamp (watts) Energy Star Qualified CFL (approximate equivalent watts) Minimum Light Output (lumens) 40 60 75 100 150 9 -13 13 - 15 18 - 25 25 - 30 30 - 52 450 800 1100 1600 2600 *Courtesy of NRCan/OEE Disposing of Compact Fluorescent Lamps Compact fluorescent lamps include very small amounts of mercury, less than 4 milligrams per bulb, which is 100 times less than what is found in your typical amalgam dental filling. However, care should be taken to dispose of CFLs safely. Most municipal jurisdictions have recycling programs that include facilities for accepting mercury products. All levels of government are working with CFL manufacturers and major retailers to expand lighting recycling options. Homeowners should contact their local municipality or electricity supplier for the closest recycling depot. Energy Star qualified CFLs have a warranty so be sure to return the bulb to your retailer if it fails within the warranty period. 87 Appendix B. Environmental Impacts of Lighting Energy Efficiency 88 Your feedback and comments are appreciated. Please provide suggestions to: info@ceati.com Energy Efficiency is Good Business • Economic Prosperity • Environmental Performance • Social Responsibility • Security