Insulate the Attic
A properly insulated attic saves on heating bills and can help keep the house cooler in the summer. Blanket or batt insulation, 16" to 24" thick and with or without a vapor-retardant foil backing, fits between the joists and may be laid over older insulat
Wear dust mask, long sleeves, goggles, work gloves. Have plywood handy, long enough to span three joists, to stand on. Remove old insulation if flattened or moldy. Seal drafty spots with appropriate spray foam. If there is no existing vapor barrier, choose foil insulation batts, or line between the joists with 4- to 6-mil polyethylene sheeting; staple to attach. Cut holes around lighting or electrical fixtures.
Use baffles to keep insulation away from soffits (don’t cover them) to allow ventilation in your attic. Baffles come in 4' lengths and range between 14 ½" and 22 ½" wide. Choose a snug fit for your rafters. Place baffles between rafters, starting from the point where rafter and joist meet. Staple edges. When you’re ready, batts of insulation can be laid directly next to baffles. Box out lighting fixtures: covering with batts presents a fire hazard.
Working from the outer edges of the attic toward the exit, roll batts between joists. Cut to length with a utility knife. Run new batts perpendicular to any old insulation to cover any gaps. End joints should abut, but not compress each other. Cut insulation to fit around obstructions; don’t stuff it, which decreases effectiveness. Lift wires or cables and place batts beneath them. Run another layer perpendicular to the first if needed.