Attic Access Insulation and Air Sealing

Adequately insulating and air sealing the access to an attic— especially to unconditioned attics—will help lower your heating and cooling bills.

A home's attic access, which could be an attic hatch, pull-down stairs, or a knee-wall door, often goes uninsulated. This gap in the attic insulation increases heat loss in the winter and heat gain in the summer.

These accesses also often aren't sealed properly. A 1/4-inch gap around the perimeter of an attic access can potentially leak the same amount of air supplied by a typical bedroom heating duct.

Attic Stairs Cover Box

To insulate your attic stairs access, we can construct a lightweight, moveable box that will rest on the stair frame from the attic side.

Attic Hatch

An attic hatch or scuttle hole is simply a removable portion of the ceiling that allows entry to the attic. A scuttle hole is often located in a closet or main hallway.

For air sealing, weatherstripping can be installed either on the hatch itself or on the inside of the trim or base where the hatch rests. Adding a latch bolt will help ensure a tighter seal.

After the trim or base is aligned to seal properly, insulation should be added to the attic side of the hatch. Rigid insulated sheathing is recommended. Cut the insulated sheathing 1/4 inch smaller than the hatch size to allow for clearance when moving the access panel. Apply 3 or 4 inches of insulation to the hatch with construction adhesive and screws.

As an added measure, glue the kraft-paper side of batt insulation to the top of the last layer of rigid insulation. Try to achieve the recommended R-value.