DRAFT GreenPoint Rated Existing Home Rating Manual version 6.0 | Page 57

G. PLUMBING
G1. EFFICIENT DISTRIBUTION OF DOMESTIC HOT WATER

CRITERIA FOR QUALIFICATION Up to seven points of credit are available for the following: G1.1. Insulated Hot Water Pipes (1 Point)

Insulate all hot water pipes using one of the following methods: ? ? Install a minimum of one inch thick foam on the entire run of the hot water piping system for all pipes with a diameter of two inches or less, and a minimum of one and a half inch thick foam for all pipes with a diameter greater than two inches. Bury pipes in blown-in or foamed-in insulation. This is less effective than insulating the pipes directly, but is a lower-cost option for insulating piping run through attics, floors, and walls. Piping must be surrounded with at least one inch of insulation. Any required strapping must be installed so the piping is fully surrounded by insulation. It is not necessary to insulate the piping as it passes through structural framing members.

Pipes must have pipe installation if they are within an uninsulated cavity (including interior walls) or in a cavity with batt insulation (which does not fit tightly around pipes). Note: This measure is a requirement associated with measure Error! Reference source not found., “Error! Reference source not found.,” on page Error! Bookmark not defined.. This credit is a prerequisite for all other measures in section G1. G1.2. WaterSense Volume Limit for Hot Water Distribution (1 Point)

To satisfy this measure, the volume limit for hot water distribution must meet the EPA WaterSense Standards. The water temperature at the farthest fixture from the hot water source must increase a minimum of 10 degrees Fahrenheit within 0.6 gallons of flow. This volume limit will result in a wait time of approximately 15-30 seconds for hot water. G1.3. Reduced Wait Time for Hot Water (up to 2 Points)

Hot water at a temperature of 105 degrees Fahrenheit shall arrive at any fixture within the following threshold: ? ? 1 point for 10 seconds (or approximately 6-7 cups of water) 2 points for 5 seconds (or approximately 4 cups of water)

All fixtures must comply. The system must be designed to be able to achieve this threshold. These thresholds meet or exceed the standard for acceptable performance time for delivery of hot water established by the American Society of Plumbing Engineers (ASPE). G1.4. Recirculation Pump (2 Points)

Note that measure G1.1 is a prerequisite for this measure. GreenPoint Rated Existing Home Rating Manual Version 6.0, September 2013 © Build It Green

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