Started and Finished: Summer 2017


  • Seal attic with polyurethane foam to bring it inside the envelope of the house. (completed)

Contracted out

Encapsulation project

We decided we needed to cut our heating and cooling costs, so in the summer of 2017, we had our attic encapsulated.  This involved sealing up the gable vents and applying two-part polyurethane foam and fire retardant.  If I had been smarter, I would have done more pre-work prior to spraying.  In particular, the returns for the upstairs air handler should have been replaced prior to spraying.  The returns were old, leaky, filthy dirty, 6 inch flex ducts.  Two of the ducts were barely connected (basically not connected) and the third one had a good sized tear in it, so really they were returning air from the attic, which as we know isn’t what we want (You can see the flex ducts in the pictures below).  After the spraying was finished, I cut in a couple of vents and now have a relatively comfortable attic.  Since this was going to be the future home of my network equipment it was pretty important to have it cool.  I rough finished in the south end of the attic for storage space.  I put up drywall but didn’t tape or mud and put some shelving in so I would have someplace to put all my stuff from the kitchen.  The flooring in the attic was just ½ inch OSB.  I left it as is, but plan on putting plywood over it since OSB isn’t the best stuff to walk around on.  The attic will never be fully finished space, but it’ll be a great place for my network rack and storage.

Gable vents covered with 6mil plastic and OSB prior to spraying.
Prior to spraying


Spraying started. Time to get out.