How to Use DIY Foam Insulation Kits

A worker installing blown in insulation in a floor.

DIY foam insulation kits are a quick-and-easy way of reducing the amount of heat lost from your attic. Foam insulation can be used in almost any area, but it is particularly useful in areas such as attics, where small holes can cause a great deal of hot air loss. Using a spray-in foam insulation kit is much easier than attempting to fit foam insulation from a roll into tight spaces.

Varieties of Foam Insulation

There is a range of DIY foam insulation kits, including open-cell and closed-cell foams. Open-cell is more likely to allow air to fill spaces in between the foam, while closed-cell foam sets in a more rigid form and is less vulnerable to penetration from water and air.

Closed-cell foam is significantly more expensive than open-cell foam, so if you are planning to cover a lot of space, you will probably be better off purchasing the latter. If your attic experiences particularly extreme temperatures, though, you should consider closed-cell. Examples of closed-cell foam include one that's a renewable spray that causes moisture to bead and fall away. Other forms of closed-cell insulation, in contrast, absorb moisture and leach it away through openings.

Safety and Protection

DIY foam insulation kits contain toxic chemicals, so take extra care when using the spray. Protect yourself by using a breathing or gas mask, safety gloves, and clothes with long legs and sleeves. Check the area you intend to insulate for mold or rot, and don't attempt to use the foam if you see mold, but rather get it treated before proceeding.

Using the Spray

Once you have cleared your space and are properly protected, using the DIY spray foam is relatively easy. The spray combines 2 chemicals, which need to be applied evenly for proper insulation. While spraying the insulation, tread carefully on the stud boards, as stepping onto the boards between these studs can cause you to break through the ceiling of the room below.

When spraying the foam, don't spray too much in one area. Local regulations should not require you to spray more than 1-inch thickness throughout, but make sure to find out about the regulations in your area before you attempt to use DIY foam insulation spray. The foam should be left for around 1/2 an hour and then either sprayed again or covered with protective sheeting and left to keep your home warm.