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Plumbing & Water Heating

Green Building PDF Icon Combination Water and Space Heating Systems (Build It Green fact sheet, .pdf)
Combination water and space heating systems use a high efficiency water heater or central boiler to supply heating energy to the space heating system while still meeting the needs for domestic hot water. The space-heating component can be accomplished with either a forced air system or a radiant heat system. A forced air system can either use hot water piped to individual fan coil units in each unit or the hot water can be sent to a central heat exchanger and fan coil unit that then sends hot air to the individual units. Read on to learn more.
Green Building PDF Icon HDPE Piping (Build It Green fact sheet, .pdf)

HDPE pipe is a primary alternative to PVC (polyvinyl chloride) pipe for all piping applications. Unlike PVC, HDPE piping does not contain know contaminants such as chlorine and dioxins, it also has a much higher recycling rate.

This fact sheet discusses: environmental considerations such as energy, water, resource, and health impacts; practical considerations such as cost, specification, and maintenance info; and applicability to various Green Building Guidelines and Rating Systems
Green Building PDF Icon Residential Water Heating (Build It Green fact sheet, .pdf)

The delivery of hot water comes at a high price, as gas water heating accounts for about 16 percent of the average California home utility bill, and electric water heating about 28 percent. Read this fact sheet to learn how different water heating options compare in cost, performance, and energy efficiency:

  • Storage/Tank-Type Water Heaters
  • Heat Pump Water Heaters
  • Tankless Water Heaters
  • Combination/Combo Space and Water Heating Systems
  • Solar Water Heating
Green Building PDF Icon Tankless Water Heaters (Build It Green fact sheet, .pdf)
Since tankless units heat water only as needed, they are also referred to as Demand, Instantaneous, or Flash heaters. While they've historically been popular in Japan and Europe, the market for tankless units in the United States is now heating up. People like tankless water heaters because they take up less space, generally last at least 20 years, and can truly provide endless hot water if they are specified properly. Read this fact sheet to learn more about the benefits and drawbacks of tankless water heaters.
Green Building Link Icon  Energy Efficiency and Renewable Energy (Drain-Water Heat Recovery)
Any hot water that goes down the drain carries away energy with it. That's typically 80-90% of the energy used to heat water in a home. Drain-water (or greywater) heat recovery systems capture this energy to preheat cold water entering the water heater or going to other water fixtures.
Green Building Link Icon  Energy Efficiency and Renewable Energy (Solar Water Heaters)
Solar water heaters, also called solar domestic hot water systems can be a cost-effective way to generate hot water for your home. They can be used in any climate, and the fuel they use, sunshine, is free.
Green Building Link Icon  EPA (High-Efficiency Toilets)
Toilets are by far the main source of water use in the home, accounting for approximately 30 percent of residential indoor water consumption. Toilets also happen to be a major source of wasted water due to leaks and/or inefficiency. WaterSense, a program sponsored by the U.S. Environmental Protection Agency (EPA), is helping to consumers identify high-performance, water-efficient toilets that can reduce water use in the home and help preserve the nation's water resources.
Green Building Link Icon  EPA (Showerheads)
Discussion and links to resources on efficient showerheads.
Green Building Link Icon  Flex Your Power (Water Heaters)
Consumers tend to overlook the expense of heating water for their daily needs, even though 15% of each household's energy dollar goes to heat water. Using less hot water is one of the easiest ways to decrease your water heater's energy output and lower your bills. If your water heater is less than 12 years old, follow these easy, low-cost tips for using your water heater more efficiently.
Green Building Link Icon  Got Hot Water?
The Metlund® Hot Water D'MAND® System (a high performance pump, integrated controller and electronic zone valve), requires no special plumbing. It is designed for use with any hot water heating system to provide energy and water savings. It's easy to install in new or existing homes or businesses.
Green Building Link Icon  National Multiple Family Submetering and Allocation Billing Program Study
A submetering study showing both the water conservation seen by submetering water utilities, and the potential implications if it were more widely used.
Green Building Link Icon  NFS International (Plumbing)
A discussion of the different piping options available.
Green Building Link Icon  Taco Hydronic HVAC Systems
Manufacturer of Hydronic HVAC systems.
Green Building Link Icon Tool Base (Demand (Tankless or Instantaneous) Water Heaters Overview)

A general overview of tankless water heaters including a discussion of their application in green building, how to select appropriate models, and cost.