Most insulation lasts 15 to 20 years, but it really depends on the type of insulation. Spray foam is a permanent insulation material that can last up to 100 years. Fiberglass and cellulose typically settle, shift, or deteriorate around 15 years. Once your insulation reaches the 15-year mark, it's time to check it for signs of needing to be replaced.

Spreading tin foil over your windows works similarly to radiant barrier insulation, but not as well. It will reflect some of the sunlight that would otherwise come through the glass and warm up the inside of your home, so it might help a little to keep your home cool in the summer. However, the appearance isn’t preferable to blinds or drapes that can offer the same benefits. You might also consider tinting your windows instead, which is a more aesthetically pleasing change that can still block a good portion of the solar heat coming through your windows.

The most affordable way to insulate a garage involves choosing cost-effective materials like fiberglass, which comes in batts or rolls and is relatively easy to install. You can often install this type of insulation without needing to add drywall, which helps reduce costs. While a DIY approach might seem cheapest, hiring a professional installer can be highly cost-effective. Experts can accurately determine your garage's specific insulation needs and ensure the best results for your investment, often using batt insulation for the bulk of the project.

If you plan to heat or cool your garage, you’ll need to insulate the garage ceiling. Insulating your garage ceiling will make your garage much more energy efficient and save on heating and cooling costs. Not only does insulation make your garage more energy efficient, it helps reduce noise and can extend the life of your garage roof. You can use fiberglass, cellulose, mineral wool, or spray foam insulation for this project.