How To Air Seal Attic Knee Walls

Cover the insulation with a sheet material drywall or rigid foam insulation that is caulked where it meets the plywood floor sheathing which is extended to the outside wall.

How to air seal attic knee walls.

Fiberglass batts work best if they re enclosed and air sealed on all 6 sides. Video done by arlington home energy efficiency team during a weatherization barnraising in march 2010. We want to air seal any penetrations or top plates as we do in all attic spaces. Anytime i conduct an energy audit of a cape cod or 3 story colonial or a salt box i know that a good chunk of the homeowner conversation and audit report will deal with the knee walls.

Small air leaks into uninsulated attic space are a major source of heat loss in many homes. Square hole that s acting like a chimney drafting expensive heated. Chances are your ceiling has the equivalent of a 2 ft. The only air leakage in the stud cavities is typically the outlets light switches and access panels.

Air sealing an attic kneewall the approach used in the video is opposite to what i am thinking of doing. It is important to choose an air barrier and insulation material that will reduce the air leakage and heat loss as much as possible. Continue the insulation along the roofline to the roof edge figure 1. We deal with knee walls in 1930s 1950s all the time 2 3 month at least.

Adding a rigid foam air barrier to the cold side of the batt is a great way to take care of this issue on a knee wall between finished and. But then for the knee wall it s important to air seal the wall with tyvek or foamboard. How to air seal a knee wall in a cape. How to air seal knee walls along the roofline.

Installing batt insulation that extends into the attic past the 2 4 studs making sure it doesn t flop over into the attic by adding some kind of bracing and then adding a 2 piece of rigid board insulation on the non attic side of kneewall. Insulate and air seal the ceiling of the attic room. I disagree with you albeit not that strongly no fight club here that a really solid air seal is necessary over the stud cavities in knee walls. Improving attic knee wall insulation install rigid foam for added energy efficiency.

Knee walls are among the biggest air leakage and heat loss sources in home in part because they are such a pain in the rear to insulate and air seal properly. Air seal an attic series. Here s how to locate the leak spots and plug them without spending a lot of money.