If you want to insulate your garage walls against seeping of gasoline and motor vehicle fumes, you need to first check out the walls to find out if they have any crack, gap and hole. Additionally, check out the bottom of the wall and establish if it has been affected by gas and fume seeps.
Once you have completed all this, you can start making air sealing. The process only costs you silicone caulk and an accompaniment of other necessary materials.
After you are done with the walls, you need to focus on the bottom of the wall. Run a bead of silicone caulk along the wall bottom where the wall’s wood meets the concrete. Make sure that the fumes are totally sealed out by pressing the caulk into the crevices. Rubbing your fingers along the wall will smooth the caulk and ease this process. Once through with the above, turn your focus onto the cavities and perform air sealing on them too.
If your garage wall is attached to your home, the insulations need to be fixed backwards. You can use fiberglass insulation that is specially designed for such purposes and it comes with a vapor retarder. You need to install the insulation with the paper side of the fiberglass facing inhabited walls. If you are installing it from outside the wall, install it with the its fuzzed side facing you.
However, if you are fixing it on walls that do not have people living inside, you will do it with the paper side facing you. Make sure that the insulation’s paper planes are properly stapled on the studs’ edges so that the insulation can fill the cavities properly.