Subsection R403.3.4 of the International Energy Conservation Code is hereby amended to read as follows:

R403.3.4 Duct leakage (Prescriptive). The total leakage of the ducts, where measured in accordance with Section R403.3.3, shall be as follows:

1. Rough-in test: The total leakage shall be less than or equal to 4 cubic feet per minute (113.3 L/min) per 100 square feet (9.29 m 2) of conditioned floor area where the air handler is installed at the time of the test. Where the air handler is not installed at the time of the test, the total leakage shall be less than or equal to 3 cubic feet per minute (85 L/min) per 100 square feet (9.29 m2) of conditioned floor area.

2. Postconstruction test: Total leakage shall be less than or equal to 4 cubic feet per minute {113.3 L/min) per 100 square feet (9.29 m 2) of conditioned floor area. On the postconstruction test, it is permissible to test for “leakage to the outdoors” versus a “total leakage.” Leakage to the outdoors shall be less than or equal to 8 cfm per 100 square feet of conditioned floor area.