Vapor barriers in attics are a bit outdated and most areas no longer recommend them for attic spaces. For vented attics, the best method is usually to install drywall and cover it with latex paint before attaching insulation fiberglass, cellulose, or foam insulation. When renovating an attic to use as a living space, a contractor can guide you on the best way to cover insulation.

It is usually possible to install insulation yourself, but it’s often better to hire an insulation professional. An experienced insulation pro can determine which type of insulation is best for your space and the R-value get the most value and comfort in your home. Certain types of insulation can cause skin, eye, and lung irritation, and a professional will have the equipment necessary to keep themselves safe and limit the effect on your indoor air quality after the installation. Certain types of insulation—like blown-in and loose-fill insulation—demand a professional for proper functionality and safe installation.

If you’re a savvy DIYer around the house, own the basic tools, and have enough time on your hands, you can definitely install fiberglass insulation yourself. Doing the work yourself will certainly keep overall insulation costs down. However, if you’re not confident in your handy skills around the house, call in a professional.

If you plan on heating your garage, you must install a vapor barrier when drywalling the garage. A vapor barrier protects your garage from frost and mold that can occur through condensation. If your garage is unheated, you don't need to install a vapor barrier. The only exception is if you regularly crank the heat in your car before getting in it. In this case, you may still want to install a vapor barrier, as your car can heat your garage.