Attic Insulation Options and Measuring

    Published: 06-16-2009
    Views: 35,324
    Home Repair Expert Gale Tedhams discusses attic insulation options and measuring.

    Gale Tedhams: Hi! I am Gale Tedhams and I am from Owens Corning. I am here today to talk about how to add insulation to your attic. First let's look at some of the insulation product options that you have. The first product we have is Fiberglass loose-fill insulation. A loose-fill insulation is blown in through a machine and through a hose up into the attic, and it expands many times the volume of this package.

    Fiberglass insulation is naturally non-combustible, it doesn't support food, it's not a food source for mole, it won't rot, and it will last the life of the home and perform for the life of the home. Now the second thing we have is a Batt insulation, and that's like a pillow of fiberglass insulation, and it comes in a couple of forms. One in a roll, this is a one piece roll, and also batts in bags which is precut batts, this one in particular has eight pieces and they're cut to 48 inch in length.

    You notice also that they're faced, and what that means, is that on the back of the insulation as a paper vapor-retarder. Now it's important to know that if you already have insulation in your attic, you don't need it and you shouldn't use a vapor-retarder, because the vapor-retarder would be between the layers and it might trap moisture there. However if you have no insulation at all, you need to check with your local building codes, a vapor-retarder might be required. If it's required use this, and if not, you can use this or you can use the unfaced product. So, if you look at the roll here, it's got a lot of information for your project, this package is a roll batt, it's one piece and it's 25 feet in length, it's in R-30 and made for attics and flat ceilings. So you can look at the package to see what you need for your project. So now that we know what options we have for insulation, we can go ahead and measure to see what we need.

    First of all, measure the depth of insulation that you already have, and calculate how much you need to get to the top of your floor joist as well as to the total amount of insulation that you are going to use. The DOE, the Department of Energy recommends to have up to and R-60, and this depends on what climate zone, and where you live in the country. Now an R-60 is 19 inches of batt insulation, and 22 inches of loose-fill insulation. So those are numbers that you need to have in mind. The next thing is that you need to measure the square footage of your attic, and you do that by measuring the length and the width, and multiplying those two numbers together. Finally, you need to measure between the joist to know what that distance is, if you are using batt insulation, typically homes are 16 to 24 inches on center. So we've learned about the measurements, and the selection of products that you have. So now we are ready to start insulating.