Insulating and Sealing Your Attic Access

Even in a well-insulated home, one of the most com­mon and overlooked areas for an inadequately in­sulated space may be the access to the attic. Your home’s attic access, which could be an attic hatch, pull-down stairs or a knee-wall door, is often uninsulated. A one-quarter inch gap around the perimeter of an entry can potentially leak the same amount of air supplied by a typical bedroom cooling and heating vent.

But before insu­lating the area, you should first deter­mine the recom­mended insulation R-value. An R-value indicates insulation’s resistance to heat flow – the higher the R-value, the greater the insulat­ing effectiveness.

The location of your attic entrance will affect how or whether it should be insulated. For example, if the access is in a garage where the attic is uninsulated, you can eliminate the need for insulation, but if the entrance is in your home, such as in a hallway, you may need to invest in insulation.

Attic hatches, or scuttle holes, are the most common forms of access and easily fixed for energy efficiency. The hole is simply a removable portion of the ceiling allow­ing entry to the attic and is most likely located in a closet or main hallway. Usually, they are constructed from thin wood or drywall, neither of which provides any substan­tial resistance to heat loss. For sealing, weatherstripping can be installed either on the hatch itself or on the inside of the trim or base where the hatch rests. For insulation, attach a piece of fiberglass batting (the easiest material to use for this type of opening) on top of the hatch. Add a latch bolt to help ensure a tighter seal.

When gaining attic access through pull-down stairs, the frame encasing the stairs fits in an uneven opening and leaves a gap, much like a door or window, which must be sealed. If the gap is small (less than half an inch), caulk can be used as a sealant. If a larger opening exists, then a non-expanding foam or a backing material is suggested in combination with the caulk. Although expanding foam can be applied, be cautious because of its highly expansive nature, it could potentially distort the frame and obstruct the ability of the stairs to open and close correctly.

Furthermore, to insulate attic stairs, a moveable box can be constructed from rigid foam or fibrous duct board to fit over the stairs from the attic side. For added insulation, attach a piece of fiberglass batting on top of the box. Insulating kits are also available through weath­erization suppliers or from local hardware stores.

A knee-wall door is typically a partial size door that is usually found in the upstairs level of finished-attic homes. These doors are often poorly insulated and un­sealed around the frame. Make sure the knee-wall door is weatherstripped around the frame and insulate the attic side of the door. Add a latch that pulls it tightly against the frame to achieve a solid seal.

A well-insulated and sealed attic access will prevent air leakage in your home, thereby reducing energy costs and preventing discomfort. Most attic insulation and seal­ing systems require minimal time to install using simple tools and techniques. And as with all home projects, be sure to follow the manufac­turer’s instructions for proper installation and safety.