How do I Insulate a Vaulted Cathedral Ceiling?

Insulating a vaulted ceiling can be problematic -- it's difficult to work with long sections of insulation overhead. By cutting the insulation into more manageable pieces, the job will be easier and you'll be done sooner. Roofs insulated with fiberglass must be properly vented. Make sure you have at least 1 inch of air space between the top of the insulation and the bottom of the roof sheathing. Allow the better part of a day for a typical room, and make sure to have a helper available.

Things You'll Need

• Dust mask or respirator
• Safety glasses or goggles
• Gloves
• Paper-faced fiberglass insulation, 22 1/2 inches wide
• Stapler
• Staples
• Utility knife
• Measuring tape
• Ladder

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Instructions

1. • 1

     Measure the distance from the top of the wall to the peak of the ceiling. Cut sections of insulation to fill this space, using the utility knife. The insulation will be easier to work with if you use sections that are 5 to 6 feet long.

   • 2

     Staple the insulation to the bottom of the rafters or trusses. Fold out the paper flange on the edge of the insulation, and staple it to the face of the framing. Use one staple on each side, every 12 inches along its length.

   • 3

     Continue in this fashion until all of the ceiling bays are insulated.