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■ BY ROB YAGID I recently spent a day pulling wire with a friend who’s an electrician in New York. Late in the afternoon, our conversation turned to a client and friend of his who was seeking advice about insulating her new home. The topic caught the interest of some other guys on site, most […]

The first step to determining your upgrade options is to learn the type and amount of insulation, if any, in your walls. Houses built before 1930 often were left uninsulated, so you will find either empty stud bays or insu­lation that was added later. Houses built in the ’40s, ’50s, and beyond typically were in­sulated, […]

■ BY JUSTIN FINK W hen it comes to insulating floors, walls, and ceilings, nothing makes it easier than working with the blank canvas of a newly framed house. The walls are wide open, so contractors can add any type of insulation they want to achieve the best pos­sible thermal performance. What about the rest […]

A division of labor keeps insulation flowing. One person handles the hose, and the other feeds the blowing machine. The most critical job is at the machine (see the top left photo below and the bottom right photo), where the steady rate of insulation flow is controlled by the operator. At the other end of […]

The attic access is a big leak that can be fixed quickly: Build or buy an insulated cover for the access bulk­head. The key is to provide a rim to connect to the sealing cover. The rim can be made from strips of sheathing, framing lumber, or rigid foam; then the cover sits on top […]

Recessed lights are one of the most overlooked sources of air leaks into attics. The best choice is to change old can bodies (1) for airtight insulation-contact-rated (IC-rated) models (see the photo at right) and then seal the rim to the drywall with foam or caulk. IC-rated lights that aren’t airtight can be sealed by […]

U sually, the greatest number of leaks comes from small perforations in the ceiling: metal electrical boxes, drywall seams, and any place a wire or pipe comes through from below. Use expanding urethane foam to seal holes around PVC vent pipe (1), in electrical boxes (2), and especially at ceiling-corner drywall seams (3). If any […]

T here’s usually a 2-in.-wide gap, required by code, between framing and masonry chimneys. To close the gap, I first stuff it with rockwool (1), then apply a bead of adhesive caulk to the framing (2). Next, I screw down wide strips of metal (recycled drip edge)along the perimeter (3). I seal the metal to […]

The two types of insulation that are usually found in older attics are fiberglass batts and loose-fill cellulose. For batt insulation to perform at its rated level, it must be installed snug to the ceiling surface and to the edges of the framing. Any gaps or voids reduce the insulation’s effectiveness. If the existing insulation […]

Air leaks can account for 30% of a home’s energy loss, so it pays to seek out and seal every penetration between the living (condi­tioned) space and the attic (unconditioned) space before adding insulation. Don’t leave any batt unturned when hunting down air leaks. Dust deposits in leaking air stain in­sulation brown or black, so […]