Plumbing
REVIEW
Green Professional Building Skills Training
How are plumbers uniquely
positioned to help the environment?
Efficient plumbing contributes significantly to the
conservation of water.
By saving water, plumbers also save energy
(less energy for heating, treating, and pumping)
and reduce pollution (less sewage).
1 GREEN PLUMBERS NEEDED
Page 1
How do the four main 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 GREEN PLUMBERS NEEDED
Pages 2-3
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 GREEN PLUMBERS NEEDED
Page 3
Why does the current cost of
water not reflect its true cost?
The current price of water is falsely low. It
does not include the cost that local
governments pay to extract or treat water. It
also does not include the environmental
consequences of extracting water.
1 GREEN PLUMBERS NEEDED
Page 4
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 GREEN PLUMBERS NEEDED
Page 4
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
Pages 6-7
What are the issues that a plumber
might be involved with on a green
job?
•
•
•
•
•
Reducing water consumption
Installing water reuse systems
Increasing energy efficiency
Improving indoor air quality
Removing items from the waste stream through
recycling
• Being involved with the commissioning process
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Pages 6-8
Describe LEED, WaterSense,
and ENERGY STAR.
LEED: Green building certification program
WaterSense: Labeling program created by the
U.S. EPA. Promotes water-efficient products.
ENERGY STAR: Labeling program created by the
U.S. EPA and DOE. Promotes energy-efficient and
water-efficient products.
2 SUSTAINABILITY IN PLUMBING SYSTEMS
Page 8
What are the benefits of highefficiency fixtures and appliances?
• Use less water
• Use less energy
• Protect water resources
• Reduce water and sewer bills for owners
• Eliminate the need for municipalities to
expand wastewater treatment facilities
3 SAVING WATER BY REDUCING DEMAND
Page 16
What are the benefits and concerns of
installing low-flow showerheads?
Benefits: They are much more water-efficient and
energy-efficient than older showerheads.
Concerns: Traditional mixing valves were designed
to work at a certain flow rate. If the flow rate is
reduced with a low-flow showerhead, the valve may
not adjust properly. This will result in an output of
scalding hot water or very cold water that could
injure the user.
3 SAVING WATER BY REDUCING DEMAND
Page 20
What are the issues associated with
tempered faucets? How can they be
made more efficient?
Running a tempered faucet while waiting for the water to
warm wastes water. The hot and cold water streams go
down the drain while waiting for the hot stream to warm up.
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 SAVING WATER BY REDUCING DEMAND
Pages 19-20
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 SAVING WATER BY REDUCING DEMAND
Page 22
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 SAVING WATER BY REDUCING DEMAND
Page 23
How do waterless (no-flush)
urinals work?
Oil is less dense than water and will always float on
top of it. Waterless urinals retain a quantity of oil in
the fixture trap (called trap seal fluid). The oil acts as
a seal that keeps sewer gases from entering the
building. When urine enters the trap, it passes
through the oil and emerges on the other side in the
drain line. Because the trap oil is less dense than
urine, it remains behind and creates a seal.
3 SAVING WATER BY REDUCING DEMAND
Page 24
What new technologies contribute 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 SAVING WATER BY REDUCING DEMAND
Pages 25-26
What opportunities are out there to make
fire protection green?
• Water-mist systems reduce water use and reduce
runoff (which can have chemicals and toxins)
• Water can come from reclaimed or recycled
sources
• Residential fire protection systems may use the
existing potable water system to reduce piping
• Water from fire protection systems’ required
annual test can be captured and reused
3 SAVING WATER BY REDUCING DEMAND
Pages 27-28
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 31
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 32
How is hot water circulation piping designed in
the construction of new or larger buildings? What
measures can be taken to increase efficiency?
Hot water circulation is 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 on the return line. It pumps water through
the hot water piping and back to the heater on the return line.
When the circulating pump runs constantly, it wastes energy. The
pump can be controlled by an aquastat (a switch that turns on
and off, depending on water temperature) or set with a timer (to
run at specified intervals or scheduled times).
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Pages 35-37
What are the benefits of water
metering?
• 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
Page 35
Describe benchmarking.
Benchmarking is establishing a baseline of
water use over the course of a full year, then
comparing that to future annual patterns of use
or to average usage in similar buildings.
Benchmarking helps building managers
identify potential savings and prioritize
necessary improvements.
4 IMPROVING WATER DISTRIBUTION SYSTEMS
Page 37
What problems are associated with
stormwater?
• Harms the environment and local communities
• When it picks up oil, fuel, and pesticides, can
contaminate water resources, threaten lives and
property
• Causes combined sewer overflows (CSO) (a mix
of stormwater and sewage), which are
responsible for contaminating drinking water,
polluting fishing areas, and closing public
beaches
5 STORMWATER CONTROL AND DIVERSION
Page 39
How do municipalities use treated
stormwater?
In places where groundwater sources have been
depleted, municipal wastewater can be used to
replenish groundwater in aquifers. This happens
indirectly through infiltration basins or directly
through pumping water into the aquifer.
It can also be routed directly to water treatment
plants, where it gets treated to potable water
standards.
5 STORMWATER CONTROL AND DIVERSION
Page 40
What are the differences between
stormwater retention and detention?
Stormwater retention: stormwater is
captured and held until it’s absorbed into the
soil and/or evaporates
Stormwater detention: stormwater is
captured, retained, and then slowly released
over time to the storm drain
5 STORMWATER CONTROL AND DIVERSION
Page 41
State the different methods of controlling
stormwater that use bioretention.
Bioretention uses soils and plants to remove
pollutants from stormwater runoff and slow its
flow. Methods include:
• Rain gardens
• Bioswales
• Stormwater planters
• Permeable pavement
• Constructed wetlands
5 STORMWATER CONTROL AND DIVERSION
Page 43
How do blue roofs and green roofs
contribute to stormwater management?
Blue roofs: Detain rainwater in order to manage
stormwater. The roof system captures rainwater on
the roof and temporarily stores it, then slowly
releases a controlled flow through the storm drainage
system at a pre-determined rate.
Green roofs: The roof landscaping naturally captures
rainwater and allows it to slowly infiltrate plantings.
This decreases the amount of water entering the
storm drain.
5 STORMWATER CONTROL AND DIVERSION
Page 43
Describe the different forms of
constructed wetlands.
Interior wetlands
•Living Machine® treats wastewater
Exterior wetlands
•Surface flow wetlands: Have shallow basins that allow
wastewater to slowly flow from basin to basin, eventually
clarifying the waste, which is then released.
•Subsurface flow wetlands: Waste flows through a
substrate (sand and gravel) to clarify the wastewater and
eventually release it as clear water.
5 STORMWATER CONTROL AND DIVERSION
Page 44
How is rainwater different from
stormwater?
Rainwater: Precipitation that is collected from a
rooftop or other catchment surface. Has organic
waste.
Stormwater: Precipitation that contacts a surface at or
below ground level, and then runs off into drains or
waterways. Has more polluants than rainwater,
including chemicals.
6 ALTERNATIVE WATER SOURCES
Pages 38-39, 47
Describe rainwater harvesting
systems and their components.
Rainwater harvesting systems collect and store rainwater to
be used for non-potable uses. Typical components include:
• Roof washer/first flush diverter: piping that redirects the
first few gallons of rainwater and debris away from the
system
• Cistern/storage tank: stores the captured rainwater
• Water purification system: purifies harvested rainwater
• Low-water switch: connects to an alternative potable
water source in times of low rainfall
• Overflow piping: discharges excess water during times of
extreme rainfall
6 ALTERNATIVE WATER SOURCES
Pages 47-48
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).
The water is kept in a storage tank, and used in
non-potable systems (ex. toilets and irrigation).
6 ALTERNATIVE WATER SOURCES
Page 50
Describe the three main types of
biological digestion.
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.
6 ALTERNATIVE WATER SOURCES
Page 54
What are the typical processes involved
with blackwater treatment?
Blackwater treatment systems use the aerobic/anoxic
process to treat waste.
Steps of the treatment process:
• Collection
• Screening
• Biological treatment
• Ultrafiltration
• Ultraviolet disinfection
• Chlorination
6 ALTERNATIVE WATER SOURCES
Page 55
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
6 ALTERNATIVE WATER SOURCES
Page 56
What are the differences between
blackwater systems and reclaimed
(recycled) water systems?
Reclaimed (recycled) water systems:
• Used at the municipal level
• Treat sewage (which contains industrial process waste)
• Aerobic/ anaerobic process
Blackwater systems:
• Used at the individual building level
• Only on-site sanitary waste (contains organics and
human waste)
• Aerobic/anoxic process
6 ALTERNATIVE WATER SOURCES
Page 57
Explain the differences between
direct and indirect water heating.
Direct heating: Equipment burn fuel or use an
electrical resistance coil to heat water directly
Indirect heating: 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).
7 DOMESTIC WATER HEATING
Pages 62, 66
What are the uses of heat traps in
storage water heaters? What
forms do they come in?
In storage water heaters, hot water can circulate out of the
storage tank and into the risers that carry both hot water
and cold water. Heat traps on both hot and cold pipes
connected to the water heater tank can prevent
convection so the water does not rise up the pipes.
Heat traps can be simple loops of pipe or heat trap nipples
that only allow water to flow in the desired direction. Heat
trap nipples can use balls that float/fall in the water’s path,
or rubber flappers.
7 DOMESTIC WATER HEATING
Page 63
What are the benefits and drawbacks of
condensing boilers?
Benefits: Condensing systems are very efficient, because
the vapor condenses and releases the energy to heat water.
Drawbacks: When water vapor condenses, it combines with
products of combustion in the flue gases to form sulfuric acid.
This causes corrosion in flues made out of conventional
materials. Special flue materials must be used.
The drip of corrosive condensate water from the unit should
be treated in order for it to be safely added to the sewer
drain.
7 DOMESTIC WATER HEATING
Pages 63-64
What are the issues to be aware of
with on-demand 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.
7 DOMESTIC WATER HEATING
Page 64
What are the benefits of
cogeneration?
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
7 DOMESTIC WATER HEATING
Page 70
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.
Condenser heat recovery: Captures heat from the airconditioning systems of larger buildings and uses it to
preheat the cold water supply to the domestic water heater.
7 DOMESTIC WATER HEATING
Pages 71-72
Describe and compare flat-plate collectors
and evacuated-tube collectors.
Flat-plate collector: a solar collector that contains a
flat absorber mounted with attached flow tubes within
an insulated and glazed framed enclosure. Efficient in
full sunshine. Most commonly used.
Evacuated-tube collector: a solar collector that uses a
glass tube to enclose an absorber plate or fin and
attached tubing. Efficient in cool and cloudy weather.
7 DOMESTIC WATER HEATING
Pages 75-76
Why is code compliance important on
green projects?
Building and health codes and other local laws
often define materials and methods
permitted for construction or retrofit work.
Staying current with building codes will
ensure you are able to comply with them.
8 MANAGING GREEN PROJECTS
Pages 81-82
What are the indoor air quality work
practices specific to plumbers that need
to be followed to ensure sustainability?
Using low-VOC materials: Follow LEED specifications
for the amount of VOCs allowed
Air sealing: Seal fire stopping at pipe sleeves and
borings to reduce air infiltration between floors and zones
Moisture control: Protect against water leaks during
installation and line testing to ensure that absorbent
building materials do not get water damage
8 MANAGING GREEN PROJECTS
Page 83
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 offsite where weight tallies are taken for each material
category.
8 MANAGING GREEN PROJECTS
Page 84
What work practices should the plumbing
contractor be aware of in regards to Cx, LEED
documentation, and value engineering?
Commissioning: The plumber may have to coordinate with
the CxA, be present for pre-functional and start-up testing,
participate in troubleshooting, or complete punch lists and
corrective work.
LEED documentation: There may be extra documentation
for the Green Building Certification Institute (GBCI) at project
closeout to verify compliance with green specifications.
Value engineering: Plumbers may be required to provide
cost estimates for proposed or determined changes.
8 MANAGING GREEN PROJECTS
Page 85