For ducts to be considered as inside a conditioned space, such ducts shall comply with either of the following:
- The duct system shall be located completely within the continuous air barrier and within the building thermal envelope.
- 2.1. The air handler is located completely within the continuous air barrier and within the building thermal envelope.
- 2.2. The duct leakage, as measured either by a rough-in test of the ducts or a post-construction total system leakage test to outside the building thermal envelope in accordance with Section R403.3.4, is less than or equal to 1.5 cubic feet per minute (42.5 L/min) per 100 square feet (9.29 m2) of conditioned floor area served by the duct system.
- 2.3. The ceiling insulation R-value installed against and above the insulated duct is greater than or equal to the proposed ceiling insulation R-value, less the R-value of the insulation on the duct.