• In this video, This Old House general contractor Tom Silva demonstrates a cost-effective way to save energy.

    Steps:
    1. Measure the depth of the existing blown-in insulation. If necessary, add more cellulose insulation.
    2. Dump cellulose insulation into each joist bay and spread it evenly with a leaf rake. Be sure the insulation is slightly above the top edge of the joists.
    3. Lay batts of un-faced, 9½-inch-thick fiberglass insulation perpendicularly across the joists.
    4. Cut the batts of insulation to fit tightly together.
    5. Continue to cover the attic with fiberglass batts, including any wood subfloor.
    6. Build a storage-platform frame out of 2x10s.
    7. Fill the interior of the platform frame with fiberglass insulation.
    8. Cover the platform with 7/16-inch oriented-strand board (OSB) or plywood.
    9. To create a walkway to the platform, cover the wood subfloor with pieces of 2-inch-thick polystyrene.
    • Difficulty: Easy to moderate
      Climbing into the attic is the only challenging part
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    Video Directory

    Selected Topic/Section

      Tools List

      • 16-foot tape measure
        Tape measure
      • insulation knife
        Insulation knife
      • plastic rake
        Leaf rake, used to spread cellulose insulation
      • dust mask
        Dust mask
      • hammer
        Hammer
      • circular saw
        Circular saw

      Shopping List

      Cellulose insulation

      Un-faced fiberglass insulation

      2x10s, for framing a storage platform

      7/16-inch-thick OSB

      16d nails for nailing together 2x10s

      6d nails for nailing down the OSB

      2-inch-thick polystyrene, used to cover subfloor