In this video, This Old House general contractor Tom Silva shows affordable ways to create an energy-efficient attic.

Project details

Skill

Cost

Estimated Time

Steps for Insulating an Attic with Fiberglass

  • Cut fiberglass batts to fit tightly between floor joists.
  • Lay the fiberglass batt between the joists with the paper vapor barrier facing down toward the heated space. Lightly press the batt down between the joists. Note: When installing insulation along the eaves, be careful not to cover the soffit vents.
  • Use unfaced fiberglass batts to insulate over existing insulation.
  • Add a second layer of insulation by lying unfaced fiberglass batts perpendicular to the floor joists. Butt the batts tightly together for maximum efficiency.
  • To insulate under the attic floor, use a pump to blow in fiberglass loose-fill insulation.
  • Insert the hose under the floor and turn on the blower.
  • As the loose-fill insulation packs tightly into the space beneath the floor, it will slowly push out the hose. Turn off the blower when the void is completely filled.

Materials

  • Work gloves
  • Knee pads
  • Dusk masks
  • Safety goggles

Tools

Related

How to Insulate a Crawl Space

Tools & Materials

  • Utility knife
  • Insulation blower