How to Air Seal the Attic Access
How to air seal the attic access opening
Don Ames
Generally speaking, your home is more energy efficient if there is no big holes through the walls. The interesting part is, most of the air leaking holes were made by the contractors that built your home. The electrician bored holes to pass wire through, the plumbers drilled holes to push pipes through, the framer cut holes for windows, doors and access, and the heating man cut holes for ducts and registers.
There is one huge hole that was left by the framing contractor in the ceiling of your homes hallway or bedroom closet that allows you to get into your attic. Yes, I know – not all homes have the attic access in an interior ceiling. Some of them are in the garage gable, etc. For now, let’s assume all attic access openings are in a hallway ceiling. Where does this hallway go? Well, it usually runs between the living area of the home and the bedrooms and bathrooms. The hallway is kind of in the center of the house.
Along with the attic access, it is also customary to place the heating system return air register in the ceiling of the hallway. Placing the return air register in the center of the house is good planning. Putting the attic access and the return air register close to each other is not good planning. When the furnace or A.C. comes on, the return air grill sucks the air in the hallway, into the return air duct and back to the furnace. If the attic access opening is near and the opening leaks air, when the furnace comes on, the return air duct sucks air into the hallway from the attic access and moves that cold or warm ( depending on the season ) dirty attic air right into the heating system. Does your furnace filter get dirty in a short period of time? This could be one reason. Good planning.
Most attic access openings where designed in a hurry by the framing contractor. Then, the drywall contractor, who gets paid by the square foot, came along and threw up drywall in a hurry. A really good drywall hanger is a fast one. The making of the attic access opening and the attic access cover was not a project done with cape canavril precision.
Steps to Properly Air Seal the Attic Access Opening.
1. Grab a good stable ladder, cover the floor under the opening with an old bed sheet, put on some safety glasses, and remove the cover by pushing it up, turning it on it’s side and lowering it into the hallway. The cover may have insulation attached to the back of it so the glasses are a good idea.
2. The cover should be a piece of drywall that is attached to a piece of plywood. If you haven’t already, run down to the hardware store and purchase a set of snap locks. A snap lock is an appliance that has two parts. Attach one part to the access cover and the other part to the side of the opening. When you put the two together and latch the appliance, it pulls the two pieces together. Place a snap lock on one side of the cover and one on the other side directly across from the first.
3. Before placing the cover back in position, attach 1/4 inch, self adhesing weatherstripping to the perimeter of the cover. Place a piece of insulation up into the opening so that the insulation is large enough to stay in the opening. Put the access cover back into the opening.
4. The idea is to place the cover into the opening, lower it down in place until it sits on the lip of the opening and then latch the snap locks so the weatherstripping is compressed between the cover and the lip.
5. Want to test your attic access air sealing work? Shut all the doors and windows. Close the fireplace damper. Turn on the bathroom exhaust fans, the range fan, and the dryer if the dryer is in the house. Light an incense stick and place the stick around the edge of the attic access cover. If the smoke flutters back into the room, the cover is leaking air into the hallway. If the smoke settles quietly along the ceiling, the access cover has been air sealed.
Hope this article has been helpful, hurry back, but I won’t leave the light on for you…Don Ames