The following sections of the 2015 International Residential Building Code, Chapter 16: Duct Systems are hereby revised as follows:
(A) M1601.1.1 Above-ground duct systems.
(1) DELETE: 5. The use of gypsum products to construct return air ducts or plenums is permitted, provided that the air temperature does not exceed 125°F (52°C) and exposed surfaces are not subject to condensation.
(2) AMEND: 7. Stud wall cavities and the spaces between solid floor joists to be used as air plenums shall comply with the following conditions:
(3) AMEND: 7.1. These cavities or spaces shall not be used as a plenum for supply air or return air.
(4) ADD: 7.1.1 Return air must be ducted with metal or flex ducting.
(5) ADD: 7.1.2 When return air ducting and electrical wiring, switches or receptacles conflict metal ducting is required.
(Ord. 22-12-01, passed 12-20-2022)