Many factors impact indoor air quality and one is the quality of air that is in your garage. Standard practice is not best practice, according to Matt Risinger, master builder. In this video, Risinger points out what is most often done, and then what should be done, regarding protecting your home from garage air quality. Especially important when living space walls are adjacent to garage walls. In the garage, we find car fumes which are carbon monoxide, pesticides and gasoline. When the door is closed, the fumes that are now in the garage air, will move into your home.Risinger shows us a standard installation that includes unsafe batting insulation on the walls and ceiling. In the video, in spite of it being an active building site, the batting is already sagging, which means insulation failure. Wherever there is interruption of drywall, such as an electric panel that penetrates the sheetrock, there is potential airflow. In this house, the boxes on the inside and outside will let airflow through. Also, in the trusses of this house in adjacent areas with the garage, fiberglass batting is also used, which is not a good practice.In order to handle this job correctly, here's what should be done to air seal and insulate the garage.At the stage where the sheetrock has been hung, and we're looking at the gable area, we use a sheeting that acts as a good spray foam backer. Spray foam separates the house from the garage, which totally fills the cavity and provides true air sealing. Check the video out so you can view how Risinger also uses foam in the ceiling and other adjacent areas. This will keep all fumes out of the house. s