Requirements

HOMES, MIDRISE

Option 1. Efficient Hot Water Distribution (2 points)

Design and install an energy-efficient hot water distribution system, based on either maximum pipe length requirements (Path 1) or maximum pipe volume limits (Path 2).

Systems that use heat traces that serve a single unit or house are awarded only half credit. All heat traced piping must be insulated.

Path 1. Maximum Allowable Pipe Length

Do not exceed the maximum allowable pipe length from the source of hot water to the termination of the fixture supply pipe, as listed in Table 1a or Table 1b.

Table 1a. Maximum length of pipe

OR

Path 2. Maximum Allowable Pipe Volume

Do not exceed a maximum volume of hot or tempered water of 64 ounces (1.89 L) from a water heater or boiler with no circulation loop or heat traced pipe or in multifamily buildings a central circulation loop or heat traced pipe to the fixture, or 24 ounces (0.71 L) for hot water from a circulation loop pipe or an heat- traced pipe serving a single unit or house to the fixture.

Pipe volume is the sum of the internal volumes of pipe, fittings, valves, meters, and manifolds between the source of hot water and the termination of the fixture supply pipe. To determine the volume, refer to Table 2, which lists the volumes for specific types of tubing.

Branch volume requirements do not apply to cold water demand loads (e.g., toilets), tubs without showerheads, or stovetop pot-fillers.

Table 2. Volume of water distribution pipes, by tubing type

Option 2. Performance Test (3 points)

Case 1. Hot water source is a water heater or boiler with no circulation loop or heat traced pipe; or in multifamily buildings a central circulation loop or heat traced pipe.

To minimize wasted water before hot water is delivered, using EPA WaterSense testing procedures, verify that no more than 0.5 gallons (1.9 liters) of water is stored in any piping between the hot water source and any fixture, and that no more than 0.6 gallons (2.3 liters) of water is collected from the hot water fixture before hot water is delivered. Heat traces are only allowed in situations to prevent freezing.

Projects that meet WaterSense Labeled New Homes requirements automatically achieve this credit.

Case 2. Hot water source is a circulation loop or heat traced pipe serving a single unit or house

To minimize wasted water before hot water is delivered, using EPA WaterSense testing procedures, verify that no more than 0.25 gallons (1 liter) of water can be collected from the hot water fixture furthest from the recirculation loop,

Systems that use heat traces that serve a single unit or house are only awarded half credit. All heat traced piping must be insulated.

AND/OR

Option 3. Pipe Insulation (2 points)

Install at least R-4 insulation on all domestic hot water piping, including subslab pipes. Insulation on all piping elbows and tees must adequately insulate changes in direction.