Transcript The Fundamentals of Green Building
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% Reduce potable water for landscaping Install water efficient fixtures Use grey or rainwater, use native plants Use water conserving fixtures Reduce wastewater generation and potable water demand Reduce potable water use building wide by 30-45% Minimize quantity of stormwater runoff Use high-efficiency fixtures Maximize quality of stormwater runoff Use on-site renewable energy sources Promote infiltration with vegetated roofs, pervious paving Remove suspended solids from runoff 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 low consumption 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 high efficiency 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
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 indirect energy 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 pre functional 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