Insulating a Passive House

One of the main elements that differentiates Passive House from other “green building” styles  is the approach towards insulation.  You have to build a house that is super insulated while making sure that you don’t create moisture problems.  In our retrofit application we had 3/4 inch of XPS foam insulation on the outside of the house, and 10 inches of packed cellulose on the inside.  The cellulose is cheaper, uses less energy to produce, and also contains (safe) chemicals that discourage rodents and bugs from living in it.  In the pictures below you can see the layers of our wall assembly, as seen from the inside looking out the window, and also our air infiltration layer before we’ve insulated it and completed taping.  Keep in mind that the walls you are seeing are the second, inside walls, and that another 2×4 wall is behind the OSB plywood.  So if you’re interested in building a Passive House, get ready to do a lot of insulating and a lot of taping.

 

 

LOVE YOUR TAPE! have fun with it.