Archive for the ‘insulation’ Category


November 19, 2007

Is there a secret to installing insulation? Not really.

The first thing you need to know is that fiberglass insulation makes most people very itchy. It doesn’t bother me, but if it bothers you then wear gloves, a long sleeve shirt, and even a mask and eye protection: the fibers can get into your lungs and eyes.

The “R” rating tells you how effective the insulation is. The higher the “R” rating, the more the insulation.

However, there are someimg_8201.jpg standard ratings for different types of walls and ceilings. With standard fiberglass insulation, you’ll want R-13 for a 2×4 wall. If you try to increase that to R-19 it won’t fit into the wall, and you’ll end up trying to cram it in. You might think that’s OK, but actually when you compress the insulation it doesn’t work as well. So, just work with whats recommended:

R-13 2×4
R-19 2×6
R-30 2×10 (attic) to R-38 (attic)

One more thing you need to consider. Most sizes are sold in 16 or 24 inch widths. So if your joists are 24 inches apart, you’ll want to buy the R-30 in 24 inch by 48 inch batts.

You definitely want to insulate all exterior walls and your ceiling, but its up to you if you want to insulate your interior walls. If you do, it really won’t do much of anything to help keep your house warmer (or cooler) but it will help make that wall more sound proof. So you might consider insulating the bathroom and shower – – to keep the noise down and maybe even keep yourself a little warmer.

Generally you can push the insulation in between the wall joists or the ceiling rafters without any staples. If you’ve selected the appropriate size, the insulation should stay in place by itself long enough for you to put up the drywall.

Do not compress the insulation. It works by trapping air, so if you compress it you lower its effectiveness. Secondly, do not leave any voids between the insulation and the drywall. These gaps will allow air movement, which will allow heat transfer.

If you’re remodeling and want to add insulation under the floor, then you can staple chicken wire or string bailing wire in a zig zag pattern underneath to keep the insulation from falling out over time.

The State of California has put out some helpful videos about installing insulation (click on the hyper link to view)