Holes or gaps in ductwork will lower the efficiency of a heating or cooling system. This can make your home terribly uncomfortable. Holes in return ducts can pull toxins into your home. While holes in supply ducts can de-pressurize the house and may lead to expensive moisture and mold problems
Sealing and fixing your ductwork system will improve the overall efficiency of your home, make your more comfortable all while saving you money.
In order to comply with the IECC 2009 Energy Code the following test must be performed on all duct systems.
403.2.1 Insulation (Prescriptive). Supply ducts in attics shall be insulated to a minimum ofR-8. All other ducts shall be insulated to a minimum of R-6.
Exception: Ducts or portions thereof located completely inside the building thermal envelope.
403.2.2 Sealing (Mandatory). All ducts, air handlers, filter boxes and building cavities used as ducts shall be sealed
Duct tightness shall be verified by either of the following:
1. Postconstruction test: Leakage to outdoors shall be less than or equal to 8 cfm (226.5 L/min) per 100 ft2 (9.29 m2) of conditioned floor area or a total leakage less than or equal to 12 cfm (12 L/min) per 100 ft2 (9.29 m2) of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer's air
handler enclosure. All register boots shall be taped or otherwise sealed during the test.
Residential Energy Efficiency
2. Rough-in test: Total leakage shall be less than or equal to 6 cfm (169.9 L/min) per 100 ft2 (9.29 m2) of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the roughed in system, including the manufacturer's air handler enclosure. All register boots shall be taped or otherwise sealed during the test. If the air handler is not installed at the time of the test, total leakage shall be less than or equal to 4 cfm (113.3 L/min) per 100 ft2 (9.29 m2) of conditioned floor area.
Exceptions: Duct tightness test is not required if the air handler and all ducts are located within conditioned space.