R-49 attic insulation is recommended for this climate, and I spec R-60 for most attic floors because cellulose is cheap.  Yet my own unconditioned attic has an effective R-value of only about 20.  There is a typically settled loose-fill cellulose job from the early 80s under the floorboards.  I decided to relocate the thermal boundary to the top of the loose tongue-and-groove attic floorboards and to the perimeter of the attic floor plane, creating in effect an inverted, insulated box over the living space. I added 2” of extruded polystyrene board and covered it with OSB.  There is no condensing surface inside my inverted box.

 

      I paid special attention to the exterior top plates and (perhaps most importantly) I personally attended to or oversaw every detail.  This led me back to the inescapable truth is that attention to workmanship is the key to building performance

 

 

Views: 67

Comment

You need to be a member of Home Energy Pros to add comments!

Join Home Energy Pros

Comment by Joseph J. Ilacqua on February 23, 2011 at 9:12am
Geez, I wonder who insulated the walls on that house, Chris is taking credit for the attic, my memory isn't quite as sharp as it used to be, i can't remember

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Profile IconJohn Smith, irving yee and John James Cameron joined Home Energy Pros
6 hours ago
Home Energy Magazine posted a blog post
8 hours ago
robert jones posted a discussion

Conservation Services Group

Hello, recently I've applied to do contractor work for the Conservation Services Group. I would…See More
11 hours ago
Mike Kandel posted a discussion

BPI Releases 2014 Annual Report

BPI's 2014 Annual Report is now available for your viewing pleasure. It details several initiatives…See More
11 hours ago
Mike Kandel added a discussion to the group Building Performance Institute (BPI)
Thumbnail

BPI Releases 2014 Annual Report

BPI's 2014 Annual Report is now available for your viewing pleasure. It details several initiatives…See More
11 hours ago
Michael Dunseith commented on Paul Raymer's blog post Shades of Gray in Residential Construction Morality
""There ought to be a way for QCI inspectors to ding the contractor or the builder." When…"
Friday
Morgan M Audetat replied to William Fisher's discussion Can tankless water heaters provide hot water even when the groundwater is fairly cold?
"Great if it doesn't sweat. "
Friday
Bryan Pringle replied to Bryan Pringle's discussion Dense packed cellulose in basement?
"Vapor barrier is happening regardless, but I have a choice as to whether I use even more chemicals…"
Friday

© 2015   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service