Attached Garage Air Getting Into the House

A door between garage and house that doesn't close tight or has no weatherstripping; a fuel or paint smell indoors near that door; a bedroom or playroom above the garage; furnace, air handler or ducts in the garage; a workshop or play area in the garage.

This is about the shared wall and door, not the fuel itself (see the fuel and solvent pages for what to store and how). EPA's home-upgrade guidance says to air seal the walls and ceiling that separate the garage from living space, at a minimum: the house door (make sure it closes tightly and add weatherstripping), electrical, plumbing and duct penetrations, and cracks at the bottom of the walls. Keep the door shut. EPA's wider indoor-air guidance (the VOC and Care for Your Air pages) also says to buy only as much paint, fuel and similar product as you will use right away and to close containers tightly if they must be stored after use, and EPA's upgrade guide says never to warm up a car in an attached garage, even with the garage door open. If you spend a lot of time in the garage (workshop, playroom) or the heating/air system is there, EPA suggests a continuous-duty exhaust fan vented outdoors, and a blower-door test can show where air leaks into the house. EPA's guidance says a home with an attached garage should have working CO alarms; putting one outside each sleeping area is standard placement advice.