Plumbing
REVIEW
Green Professional Building Skills Training
What is the purpose of green
building? How does plumbing play
a critical role?
Green building is the construction industry’s
response to environmental pollution, diminishing
natural resources, and economic pressures. It
improves human and environmental health, and
decreases energy and water consumption. Efficient
plumbing contributes to water and energy
conservation which help the economy, environment,
and health of the public.
1 WHY GREEN PLUMBING MATTERS
Page 9
How do the four primary benefits of
green building relate to the plumbing
industry?
• Jobs: More green building projects means more
jobs for plumbers knowledgeable in water
efficiency strategies and retrofits.
• Environment: Decreases in water use mean
decreases in energy use and pollutants.
• Health: Using low VOC materials increases
indoor air quality
• Economy: More jobs, cost reductions from
efficiency
1 WHY GREEN PLUMBING MATTERS
Pages 9-10
Why are our current water use
practices not sustainable?
The U.S. population has increased, and so has
the demand for water. The supply of above and
below ground freshwater is diminished, and
regions of the country will soon face severe
shortages. Chemicals from agriculture and
impervious surfaces contribute to water pollution.
1 WHY GREEN PLUMBING MATTERS
Page 11
How do humans fit into the
hydrologic cycle?
Humans need to have an integrated role in
the natural cycle. It is important to be
conservers of water, to clean and reuse it
safely and smartly instead of wasting it.
1 WHY GREEN PLUMBING MATTERS
Page 11
Describe the new hydrological
cycle.
The new hydrological cycle involves the
efficient use and recycling of water, which shifts
the responsibilities of water management from
nature to humans. It includes sources of water
outside of the traditional water main or well
system, such as collected rainwater and
recycled greywater for non-potable uses.
1 WHY GREEN PLUMBING MATTERS
Page 12
How does the whole-building
approach apply to sustainable
plumbing systems?
A greater level of sustainability can be achieved
by integrating water savings and reuse elements
to create a coordinated plumbing system
dedicated to water reduction.
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Page 13
What are the issues that a plumber
might be involved with on a green
job?
•
•
•
•
•
•
•
•
Reducing water consumption
Increasing energy
Improving indoor air
Managing construction and demolition
Being involved with the commissioning process
Submitting LEED building certification documentation
Retrofitting existing buildings
Increasing maintenance to ensure operation of
complex systems
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Pages 13-14
What are the issues that a
plumber might encounter when
retrofitting an existing building?
When retrofitting an existing a building, a
plumber may replace fixtures and piping for
lower consumption and higher efficiency,
and/or install water-use meters that allow
operation and maintenance tracking.
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Page 14
What plumbing products does
ENERGY STAR certify?
•
•
•
•
•
Water heaters (gas, propane, oil, and solar)
Dishwashers
Washing machines
Geothermal heat pumps
HVAC equipment (heating, venting, and air
conditioning)
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Page 18
What are the goals and strategies for the
plumbing-related LEED new construction
credits?
Goal
Strategy
Reduce water consumption by 20%
Install water efficient fixtures
Reduce potable water for landscaping
Use grey or rainwater, use native
plants
Reduce wastewater generation and
potable water demand
Use water conserving fixtures
Reduce potable water use buildingwide by 30-45%
Use high-efficiency fixtures
Minimize quantity of stormwater runoff
Promote infiltration with vegetated
roofs, pervious paving
Maximize quality of stormwater runoff
Remove suspended solids from runoff
Use on-site renewable energy sources
Use solar thermal hot water
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Page 17
What is the relationship between
high-efficiency fixtures and
appliances, and protecting the
environment?
High-efficiency equipment conserves water
and energy. By conserving water, the fixtures
and appliances reduce the depletion of potable
water resources and the put strain on natural
ecosystems. Less energy is spent pumping,
heating, and treating water.
3 REDUCING END-USE DEMAND FOR WATER AND ENERGY
Page 19
What are the issues associated with
tempered faucets? What strategies
tempered faucets more efficient?
Running a tempered faucet while waiting for the water to
warm can cause waste. The hot and cold water streams go
down the drain while waiting for the hot stream to become
warm.
Strategies to make tempered water faucets more efficient:
• Have the circulating hot water close to the faucet
• Have a heat maintenance cable run from the
circulated line to the faucet (only if the pipe and
heat maintenance cable are well insulated)
3 REDUCING END-USE DEMAND FOR WATER AND ENERGY
Page 22
What are the differences between lowconsumption toilets, high-efficiency
toilets, and dual flush toilets?
• Low-consumption toilets use 1.6 gallons per flush (gpf).
• High-efficiency toilets are the newest and most efficient
toilets available. Their hydraulic design allows them to
flush using 20% less water, using only 1.28 gpf or less.
• Dual flush toilets offer two different flush levels: a full
bowl 1.6 gpf flush for solid waste, or smaller flush using
only 0.8 gpf for liquid waste.
3 REDUCING END-USE DEMAND FOR WATER AND ENERGY
Pages 25-26
What is the concern with high
efficiency fixtures and drain-line
carry?
Drain-line carry is the distance that water can
float or carry solids down horizontal runs. There
is concern that there will be drain-line carry
problems with older pipes because highefficiency fixtures use much less water than the
drainage systems were originally designed for.
3 REDUCING END-USE DEMAND FOR WATER AND ENERGY
Page 26
What new technology exists that contributes
to landscape irrigation efficiency? Why is
efficiency in landscape irrigation important?
Efficiency in landscape irrigation is important because the
irrigation of constructed landscapes uses a lot of water, and
has a significant impact on natural resources.
New technology:
• High-efficiency landscape irrigation systems that use
emitters, foggers, micro-bubblers, or stream jets.
• Drip systems and smart valves.
• Sensors that can measure the moisture level and rainfall
amount, and can be linked to process weather data.
3 REDUCING END-USE DEMAND FOR WATER AND ENERGY
Pages 30-31
Why is it important to insulate
hot water piping and cold
water piping?
Insulating hot water piping keeps the energy used to
heat the water from dissipating needlessly.
Insulating cold water piping prevents condensation
from accumulating, and the pipes from becoming
thermal sinks that take energy from hot water
piping and the building’s heating systems.
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Page 33
How does the trunk-and-branch
method of piping contribute to the
wasting of potable water?
Trunk-and-branch piping design contributes to wasting
because people run fixtures while waiting for water to warm.
Large trunk lines move cold water to water-heating
equipment, and when heated, smaller branches move the
water to the appliances. The hot water stays in the line until it
is used, and eventually it begins to cool. When the user goes
to access the warm water they must run the fixture down the
drain until it is warm again.
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Page 33
How is hot water circulation piping designed
in the construction of new and larger
buildings versus smaller or existing
Hot water circulation isbuildings?
often designed with a dedicated
return line from the fixtures furthest from the water
heating equipment and circulated continuously by a
pump. The recirculation line is connected to the water
heater near the cold water inlet, and the circulating pump
is installed on the return line, and pumps water through
the hot water piping and back to the heater on the return
line. An aquastat controls recirculation flow.
Smaller and existing buildings may not have hot water
circulation. Installing a dedicated return line in an existing
building is difficult.
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Pages 35-37
What are the benefits or water
metering within buildings?
• Reduces water use by providing incentive
• Helps identify system leaks
• Gives operators information that can identify
issues, and reduce water loss.
• In large buildings, installing meters to
individual supplies allows owners to charge
tenants based on their water use. This
decreases water use.
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Pages 37-38
What strategies can be used to
mitigate CSO events?
• Divert incoming rainwater into large
holding tanks or an underground tunnel
(water is later moved to a treatment plant
or water body after sediments and
contaminants have settled)
• Install green roofs
• Replace paved areas with plantings
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Pages 39-40
What are the three sources of harvested
water? What are they collected, and what
can the water be used for?
• Rainwater: Collected through rooftop
catchment mechanisms. Used in non-potable
systems, or treated and used more broadly
• Stormwater runoff: Collected in controlled
environments (ex. sidewalks, parking lots).
Used in non-potable systems
• Condensate: Recycled greywater, used in
non-potable systems
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Pages 44, 47-49
Describe greywater systems, and how
the greywater is purified and used.
Greywater is collected and then filtered to
remove solid particles. It is then mixed with a
disinfecting agent, and neutralized with
ultraviolet light in combination with a pre-filter
(typically a reverse osmosis filtration system
(RO). The water is kept in a storage tank, and
used in non-potable systems (ex. household
appliances and irrigation).
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Pages 44, 50-51
What is the primary public health
issue related to wastewater
treatment?
The control of pathogens –
dangerous microorganisms that can
cause disease in humans.
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Page 52
Describe the three main types of biological
digestion, and what type of wastewater
treatment they are appropriate for.
• Aerobic: Treats wastewater in an environment
with oxygen.
• Anoxic: Treats wastewater in an environment
without free oxygen.
• Anaerobic: Treats wastewater with a bacteria
that does not need oxygen and releases
methane gas. Commonly used in large
municipal sewage treatment plants.
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Pages 52-53
What are the risks associated
with reused water?
•
Chemical contaminants could be present
despite treatment (ex. heavy metals,
volatile organics, prescription medication)
•
Cross-connections with potable water
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Page 56
What are the recommendations of the
American Water Works Association in
terms of backflow prevention?
• The use of RPZ backflow preventers for
isolation of reclaimed water systems.
• Regular inspection to ensure that any debris in
the piping has not interfered with the function
of the assembly. Inspection intervals should
not exceed one year. Overhaul intervals should
not exceed five years.
5 ALTERNATIVE WATER SUPPLY TECHNOLOGIES
Page 57
Explain the differences between
direct and indirect heating.
• Direct heating: Equipment burn fuel or use
an electrical resistance coil to heat water
directly
• Indirect energy: Equipment use heat from
secondary sources where the heat energy
is transferred to the water heating
equipment through a heat exchanger (ex.
solar collectors, building heat system).
6 ENERGY SAVINGS
Pages 60-67
What are the issues to be aware of
with instantaneous water heaters?
• The power input for electricity (kW) or gas
(Btu/hour) for instantaneous water heaters are
higher than conventional storage-type
equipment. May require increases in the gas and
electrical infrastructure serving the units to meet
the high power requirements.
• Some instantaneous gas-fired water heaters are
the condensing type and require flue venting and
involve condensate issues.
6 ENERGY SAVINGS
Page 64
What are the benefits and drawbacks of indirectenergy water heaters? Condensing boilers?
Indirect energy water heaters:
• Benefits: Lowers capital costs because only one boiler is
needed. Can be very efficient if coupled with a
condensing boiler.
• Drawbacks: The system is limited to the efficiency of the
boiler. Heating system boilers require HVAC to run when
not needed.
Condensing boilers:
• Benefit: Highly efficient in generating hot water.
• Drawback: The cold water input line can be misplaced. It
must enter the tank at the lowest point.
6 ENERGY SAVINGS
Page 68
Describe direct flow and heat-pipe
evacuated tube solar collectors.
•
Direct flow: No air. Has two pipes that run down and back
inside the tube: one for cool inlet water, one for hot outlet
water. An aluminum or copper fin acts as an absorber plate
which moves heat to the water system in the tube.
•
Heat-pipe: No air. Has a small amount of alcohol or water
with additives, and a copper tube attached to the absorber
plate. The liquid boils, the evaporate rises in the tube, and
the heat is transferred to water in a top-mounted manifold.
The liquid condenses and flows down the tube where the
process begins again. No fluid from solar loop enters the
tube (unlike direct flow), allows for easier installation and
damage repair.
6 ENERGY SAVINGS
Page 72
What is cogeneration? What are the
benefits?
Cogeneration captures waste heat from electricity
production and converts it into useable thermal
energy.
Benefits:
• By combining heat and power, 30% less fuel can
be used.
• Environmentally friendly
• Cuts costs by generating power and hot water
simultaneously
6 ENERGY SAVINGS
Page 78
What are the forms of energy
recovery and how do they work?
• Drain-water heat recovery: Captures heat
from water entering drains. Can preheat
cold water in all forms of water heaters.
• Steam condensate heat recovery: Stores
the steam condensate in a tank and uses it
to preheat domestic hot water through a
heat exchanger.
6 ENERGY SAVINGS
Pages 81-83
What are the indoor air quality work
practices specific to plumbers that
need to be followed to ensure
sustainability?
Use low-VOC materials, air-sealing,
and moisture control to ensure
better indoor air quality.
7 MANAGING GREEN PROJECTS
Page 86
What work practices should the plumbing
contractor be aware of in regards to
commissioning?
• Commissioning may impact the work schedule.
• Plumber may need to be present for prefunctional and start-up testing of the installed
equipment for HVAC, greywater or blackwater
systems, or energy efficiency systems.
• Building flush-out requirements may involve the
plumber not being able to work inside the building
for a 2-week period.
7 MANAGING GREEN PROJECTS
Page 88
Explain the two forms of construction
and demolition waste management:
sorting and co-mingling.
• Sorting: Separating construction and
demolition waste into separate containers
based on the composition of the recyclable.
• Co-mingling: Using a single dumpster for all
recyclable materials. The materials are sorted
off-site where weight tallies are taken for each
material category.
7 MANAGING GREEN PROJECTS
Page 87