How to Lay Blanket Insulation in Your Attic - Part 3

A close-up of the end of a roll of insulation.
  • 2-6 hours
  • Beginner
  • 250-500
What You'll Need
Fiberglass blanket insulation
Utility knife
Safety gloves
Safety glasses
Vapor barrier

This article is the final part of a 3-part series that discusses how to install blanket insulation in your attic. We previously learned what blanket insulation is, insulation safety tips, how to install blanket insulation, and how to use a vapor barrier, or shield. This final article will now discuss recessed lighting and fixtures. To return to Part 2, click here.

Step 1 - Mark the Fixtures

As you install the blanket insulation, take notice of all the junction boxes and outlets that need to be exposed for future access. Use a utility knife to indicate the location of these cutouts so that you can make the appropriate cuts after you get the insulation put in. Also, make the cutouts prior to the installation of any vapor barrier, since the markings will be more visible beforehand.

Step 2 - Cut the Markings

Using the mark you made as a guide, use a utility knife to cut away the insulation covering the fixture. Make sure the blade remains sharp and that you remove all the insulation in the way of your fixture. Keep extra blades around. You will need to change them often.

Step 3 - Tuck Loose Insulation in Place

Now, tuck the loose pieces of insulation in to clean the area and make it appear more professional. Overlap the seams to help prevent any breaks or gaps through which heat or energy could escape. You can also install the vapor barrier at this point, accounting for the location of any additional fixtures.

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