Spray foam insulation is great for retrofitting and adding insulation to finished homes. With spray foam, you can add insulation without having to do much demolition or construction. It is very effective for adding insulation to interior and exterior walls with drywall siding. It can greatly increase the insulation of your home. This is useful in all climates. This article explains how to add spray foam insulation to the walls in your home.
Using the Right Product
You can find spray cans of foam insulation. Because of their limited capacity, these are really only useful for small projects. They are not sufficient if you are trying to insulate full walls, or large portions of them. You can find large capacity spray foam insulation kits that have a simple gun attached to a hose that is fed by a large tank (almost like a propane tank).
Identifying the Best Walls
Even if you use a large capacity spray foam insulation, you will not be able to practically apply the insulation to every single wall in your home. In fact, you should only apply it to the most important walls. Exterior walls can always use extra insulation, but you might want to first focus on the walls in rooms that seem to be the hottest or coldest.
Drilling the Holes
Once you have selected your walls, you need to drill holes into the drywall. The holes need to be wider than the tip of the foam gun. Drill the holes near the top of the wall. However, you need to use a stud finder to figure out the best places to drill. Try to drill the hole near the center of the space in between the studs. Most homes are built with studs that are 16" apart. By spraying the foam into the top of the wall, you can ensure that it will fall down into the cavity. You can also drill a hole near the bottom, just to check if the foam is filling in the entire cavity. Of course, the more holes you drill, the more repair work you will need to do in the end.
You will need some drywall putty and paint to patch up the small holes left behind. Hopefully you will have some leftover paint from your initial paint job. This is a nice way to increase the energy efficiency of your home with minimal time and monetary investment.