The International Residential Code (IRC) states that openings in a garage/house separation must be equipped with a solid wood door not less than 1-3/8" in thickness, a solid or honeycomb core steel door not less than 1-3/8" thick, or a 20-minute fire-rated door. If the door has a window, it must be fire-rated. If a pet door has been installed, the fire rating of the door has been ruined and it should be replaced. This door should be self-closing, and although this requirement is no longer listed in the IRC, it is still highly recommended. Openings from a garage directly into a sleeping room are prohibited. This is one rule I see violated quite frequently when conducting home inspections.
Walls and Ceilings
The garage must be separated from the residence and its attic area by not less than 1/2-inch gypsum board or equivalent applied to the garage side. A garage beneath habitable rooms must be separated by not less than 5/8-inch Type X gypsum board or equivalent. All drywall joints must be taped or sealed. If there is a non-fire-rated attic ladder installed in a garage ceiling, there must be a fire-resistance-rated assembly installed between the garage attic and the house attic.
Ducts penetrating the wall or ceiling separating the dwelling from the garage must be at least 26-gauge sheet steel or other approved material, and cannot have any openings in the garage. Quite often, I see dryer or HVAC ducts penetrating a garage wall that violate this rule.
Steve Stenros- First Choice Inspections is a CREIA MCI and ICC certified home inspector serving San Diego, Orange, and Riverside counties in southern California. Clients receive a FREE lifetime appliance RecallChek with every standard inspection. Steve can be reached for home inspection appointments at 888-335-3040. Use this article as your guide to make sure you don't let your garage/house separation burn your home down!