Synopsis: If not insulated and air-sealed properly, attic hatches can represent the single largest source of heat loss in a home. Here are the readily available materials and simple techniques that the author uses to construct an attractive, airtight, and well-insulated attic access.

I have been building airtight, energy-efficient homes for more than ten years. Before that, I built homes I thought were energy-efficient. Because I didn’t make them airtight, though, I wasn’t addressing half of the equation. Making a house airtight means closing the holes between conditioned spaces, such as the living room, and unconditioned spaces, such as the outdoors. I attack big holes first and work my way down until I reach the point of diminishing returns.

The single biggest, leakiest hole in most houses is the attic access

Often, attic accesses are no more than a piece of painted plywood on a couple of cleats. Most homeowners and builders don’t recognize how much conditioned air escapes through an attic access. The access is in the ceiling, probably in a closet, and no one notices the draft. Or they rarely connect the cold drafts on the first floor of the house with the attic access upstairs. However, this hole in the highest part of the ceiling can allow a tremendous amount of heated air to escape into the attic, creating a convection-driven stack effect just like the draft in a chimney. This heated air is replaced by cold outside air, which you might notice as a draft that enters below the front door.

In less than an hour, using just a few materials, some of which ordinarily would end up in the scrap pile, I can build an energy efficient, somewhat attractive attic access. It also doubles as a dam to prevent insulation from falling…