This tool has been created to get you thinking about how your home copes with the extremes of
temperature seen in Melbourne throughout the year. It will not provide solutions but rather, start
you exploring your own solutions to the issues you identify. Use the links at the bottom of this page
and in the tool to find out more specific information.
Navigating the maps (these will be headings with expandable lists flowing out below)
Navigate around the map to find your house using your mouse or you can type your address into the
search box in the top left corner.
To zoom in roll your central mouse button forward; to zoom out roll your central mouse button
backwards. Alternatively you can use the zoom bar on the left of the map.
The help section located in the top right hand corner can always be accessed. This has details on
how you can move around and use the maps
Turning on the tool layers
To turn on the layer that you are interested in just click on the image on the left hand side of the
page. You can move between tools at any time by using the back button.
Using the layer controls
When you enter the urban heat island or winter heat loss tool the layer
controls will appear. You can choose to view the daytime layer by clicking
on the sun, or the night time layer by clicking on the moon.
You can adjust the transparency of the layer by moving the sliding scale
directly below the sun and moon image.
When you roll over each of the magnifying glass icons a box will appear
with details about each tool. The tools are (clockwise from top left), hot
spot identification, cool spot identification, whole of rooftop query, polygon
based query, single point query.
You also have the ability to calculate an indicative cost for installing
insulation by drawing how much of your roof you would like to cover, with
the polygon tool.
Getting the most out of the urban heat island tool
The urban heat island tool allows you to see how hot your roof is getting during the day and how it
may or may not be cooling down at night. Just because your roof is hot doesn’t necessarily mean
your home is hot, but if the difference between day time and night time is only a few degrees, it may
be retaining heat during the night causing your cooling system to work harder.
By looking at surrounding properties you may be able to see an overall picture about why some
homes are cooler than others. Things like roof colour, roof type and the presence of trees are
obvious reasons why some rooves are hotter than others. What you can’t see is roof insulation and
A
B
what settings an air conditioner is on. You can however have conversations with neighbours and
friends if their roof is significantly different from yours and begin to explore the differences.
Using this image as an example we can start to ask some questions around why the houses in this
street have such different temperatures. All of the houses have rooves of similar colours (light) and
material type. So why then are the houses to the left of the image showing cool/blue rooves?
House A
House B
Midday temperature - 28.5C
Midday temperature – 67.6C
Midnight temperature – 26.3
Midnight temperature – 32.5
N.B. The maximum temperature recorded in Melbourne on the day the records were taken was 40C.
Some possibly reasons for these temperature differences:



House A
Occupants have left for work early and have closed windows and curtains to stop the
property heating up.
The air conditioning is set quite low and is on 24 hours. The cool air is leaking into the ceiling
cavity cooling the roof temperature.
The difference of 2 degrees between day and night temperatures could mean that the house
is designed very well to keep cool during the day so that limited or no cooling is needed.
House B


The difference between midday and midnight temperature could be because the house was
unoccupied during the day and cooled slightly when opened up or air conditioning started in
the evening.
The fact that the roof didn’t cool excessively could indicate that the ceiling is insulated
keeping any cool air conditioned air in the home for longer.
As mentioned earlier, this tool is about stimulating discussion with the eventual result being
changes to reduce your energy consumption and keep you more comfortable in your home.
Check out the FAQ section of the tool for some tips on creating more comfortable living
environments.
Getting the most from the winter heat loss tool
The winter heat loss tool allows you to see the temperature of your roof in winter during the day
and evening.
There are a number of reasons why your roof may be showing as blue or cool in the tool. What you
need to focus on is the difference between the day time and night time temperatures. If your roof is
absorbing heat during the day making your home warm then the daytime temperature should be
high. The ideal situation is that this stays relatively high with only a small difference of 3-5 degrees
during the night without the need to artificially heat your home.
If the drop is greater than this you may be losing the warmth gained during the day due to draughts
and lack of ceiling insulation.
If your home is showing low daytime temperatures it is not capturing the heat during the day. This
has an effect when you get home from work as the house will be cold and uncomfortable and you
will have to use artificial heating to be warm.
Different roof materials and colours affect how hot, or not, your roof gets. White rooves will be
cooler then darker colours and generally tile, slate or concrete will retain more heat than a tin roof.
When you look at the winter heat loss maps you may find that different areas of your house are
showing different colours.
This could be due to:





The roof direction (i.e. areas of the roof facing west will retain heat for longer).
Roofing product.
Overshadowing by trees or other buildings.
Whether you have ceiling insulation throughout your house or only in sections.
If you have renovated a portion of your home, the insulation levels may be greater in this
portion of the house which will also result in different temperatures.
If you have one section of your roof that is hotter than others this may be excess heat from your
chimney.
Daytime image
Using these images as an example we can start to ask
some questions around why the houses in this
neighbourhood have such different temperatures.
The rooves are quite different in this neighbourhood.
The rooves showing red in the daytime image are
generally darker tiled rooves, while those showing
blue are cool tin rooves.
The property within the circle is double story
property and the red area on the left of the circle is a
solid brick wall that is the side of the building. This
has trapped heat during the day and will release it during the evening. Although beneficial in winter,
this is not an advantage in summer heatwaves.
The blue section at the rear of the property looks like to be a single story extension. It could be
constructed of slightly different material and this could explain why there is a temperature
difference.
By using the single point query tool you will be able to check different areas on your roof for
temperature readings. You may then be able to correlate the general comfort levels you feel in your
home, with this information.
Draughts can greatly impact on the comfort levels of your home. Using the point query tool may
help you identify where there are draughts entering your home or where warm air is escaping.
Products like insulation, gap sealers and draught stoppers can help to keep your home warm.
To find out more about how to seal gaps and stop draughts check out this link:
http://www.mefl.com.au/services/sustainability-advice/insulation-and-draught-sealing/item/772draught-sealing-a-simple-way-to-stay-warm-in-winter.html
Getting the most from the solar potential tool
The Solar Potential tool allows you to predict energy generation from solar panels or solar hot water
based on location and size of the system.
The layer controls allow you to:
 Adjust the visibility of the solar radiation layer. This layer allows you
to see a series of diamonds of different colours. Green diamonds indicate
that a solar panel in this location will generate less than 3.0kWh/m2/ day.
While a red diamond indicates a location with the potential for
5.0kWh/m2/day or more.
 The Analysis tools allow you to select (L-R) a specific point on the
image to identify kWh/m2/day potential; solar panel array or solar hot
water potential.
 If selecting automatic, the tool will angle panels or hot water
system in an optimal location and then provide a report. You can increase
the width and length to suit. If you choose manual then you are able to
create a specific shape for the panels.
 The sizing of the system 1kW, 1.5kW and 5kW will generate
automatic sizing, however this can be adjusted in the height and width boxes. The size of
the system suitable for your circumstances will depend on how much electricity you
currently use and how much space you have on your roof. Bear in mind that bigger isn’t
always better. If you decide to install a 1.5kW system but half of this is covered in shade
from trees for more than half the year, then maybe a 1kW system would be more suitable.
When using the solar potential tool, you should also use the shadows tool at the top right hand side
of the tool. The shadow tool allows you to see how shadows over the course of the day in different
seasons will affect the solar potential of your roof. This is a very useful tool when first making the
decision to put a solar system on your roof.
This tool is a guide only and should not replace advice from a sola installer.
Getting the most from the rainfall capture tool
The rainfall capture tool allows you to draw a polygon over the area of roof that you would be
capturing water from. This will then provide a figure for the projected amount of water that could be
collected each year. These figures are based on current rainfall figures and do not take into account
projected future rainfall which may be different due to climate change. As the rainwater tank will
need to be placed in a certain location it is important to know that you are not under or over sizing
your tank for the amount of water you are collecting.
What if I’m renting? How can I use this information?
If you are renting your property you can still make simple changes or requests to your property
manager to seal gaps and stop draughts. There are also a number of DIY double glazing products
that won’t impact on the house.
To find out more about how to install double glazing at home check out this link:
http://www.mefl.com.au/services/sustainability-advice/insulation-and-draught-sealing/item/823how-to-install-double-glazing-plastic-on-your-windows.html