Builders don’t always insulate and seal the cover on the attic access opening, whether it’s a simple board you slide aside or part of a complete stairway. Most often, just a scrap piece of plywood or drywall cut somewhat close to the correct size is placed in the opening, and it rests on a perimeter of inexpensive molding.
This type of cover likely leaks a significant amount of air and probably has an insulation value of around R-1, which compares pretty badly to an attic that’s properly insulated to R-49 or R-60. In a well-insulated house, even a few square feet of uninsulated floor can lose a considerable amount of heat. However, because the attic access often is in the ceiling of a bedroom closet or a hallway, the air leakage and heat gain (or loss) seldom are noticeable – except on your power bill.
During summer, attic temperatures can get extremely high and the air is humid, so you don’t want it leaking into your living space. During winter, the heated air in the house, because it’s less dense, tends to leak up and into the attic.
The simplest fix for air leaks is to weather-strip the top edge of the lip where the hatch sits. Before you add weather stripping to the molding lip, place the cover over it and check whether it’s even all the way around. The lip sometimes consists of pieces nailed to the sides of the opening that aren’t level, so you may have to pry a side loose and reattach it.
Then attach insulation to the top of the cover, which should be rated the recommended ceiling R-value for your area. Find out what that is by going to www.ornl.gov/~roofs/Zip/ZipHome.html.
If you plan to go into your attic often and want to install pull-down stairs or a ladder – or your attic currently has one – buy a specially insulated cover for the attic access opening. You could attempt to make one yourself, but its weight may be hazardous to open and manage when you’re on the stairs.
One of the least expensive options is basically a three-sided, heavy-duty cardboard box. It’s easy to open and assemble, and then you can attach your own insulation to its top and sides.
This type of unit is very lightweight and easy to lift and handle when you enter the attic from the stairs.
Another lightweight, efficient option is a large, rigid-foam dome that covers the folded stairs or ladder from above. It’s strong, and the foam provides adequate insulation. Finally, check into designs that use a flexible zippered insulated cover that’s permanently attached to the attic floor for a good, airtight seal. The zipper provides a large opening for easy access to the attic.
For more information, visit www. TogetherWeSave.com, which has two videos on this subject as part of its Watch and Learn series. Go to http://
energysavings.togetherwesave.com/ watch-and-learn and click on the Sealing and Insulation tab; then scroll down to find the how-to videos on insulating attic hatches and attic pulldown stairs.
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These companies offer attic entrance products.
Rainbow Attic Stairs