DIY Projects

Project File #7
Do It Yourself
As Soon As Possible
A cost-effective project that leads to big energy savings

Make your attic rooms more comfortable by air sealing and insulating

If your attic rooms aren’t retaining temperature well, it may be due to a lack of proper air sealing and insulation. With this relatively simple project, you can make a big impact on the comfort of these rooms, and save energy in your home.

Project Overview

Tools and Materials:

  • Utility knife
  • Table or circular saw
  • Caulk gun
  • Measuring tape
  • Lights
  • Straight edge
  • Markers
  • Foam/caulk/construction adhesive
  • Cavity insulation—fiberglass batts
  • Blocking material—rigid foam board
  • Sheathing—OSB/plywood, code-approved foam board or bubble-wrap radiant barrier
  • Fasteners—screws with washer or button-capped nails


  • Dust mask/respirator
  • Gloves
  • Safety glasses
  • Kneepads
  1. Attic kneewalls help separate a conditioned attic space from the unconditioned attic. Unfortunately, if these kneewalls are badly insulated or air sealed, then they may not be doing a very good job.
  2. Add blocking first, to help prevent air leakage. Once blocking has been put in place, you can begin to airseal the space by using caulk or spray foam.
  3. Cavity insulation and sheathing can also help to further protect your attic rooms from air leakage, but should be added last.

Download Project File

Get the printable step-by-step instructions and start saving today.