With the use of Superior Walls for the basement level, what would be the best interior insulation for a finished basement?
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With the use of Superior Walls for the basement level, what would be the best interior insulation for a finished basement?
Thanks,
Dick
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Richard,
If you want to add additional insulation to a Superior Wall panel, you can install either spray foam insulation or rigid insulation. Here is the document from Superior Wall the includes the manufacturer's recommendations:
http://www.superiorwalls.com/download_doc/47/268
I seem to remember that the Superior Wall system has a configuration of thin concrete and concrete "studs" that complicates the whole-wall R-value calculation. Unless my memory is failing me, these walls have thinly insulated concrete studs that present a thermal bridging problem. My online search failed to come up with a good cross-section showing how these walls are constructed.
Superior Wall studs are thermally broken. The original version had the studs cast separately and the R-5 foam was continuous behind the stud.
The new system offers R-12.5 or R-21.3 with 1 inch of foam surrounding the studs and the top beam. (not sure the R-value on the foam around the studs).
I have used this system for about 15 years and have been very happy. It is however imperative that the builder reads and understands the instructions. This is a different system and a builder resistant to learning new things should avoid new systems. Any problems I have ever heard of with Superior Wall were the result of builder error.
As far as adding insulation, a superior wall system is probably the only place I would advocate fiberglass batt. Spray fiberglass, or cellulose are also options here. Since the "sheathing" is insulated the temperature should remain above the due point most of the time. Good air sealing should be used. If this approach makes you uncomfortable, then by alll means use open cell spray foam, or even closed cell. With no wood products in the wall there is far less danger of mold/decay than in most walls.
I recently visited a home with Superior Walls in the basement. These were the "R-12" type. I put my hand against the metal that covers the inside face of a concrete stud and was very surprised at how cold it felt. I don't know how they are measuring the R value that they are advertising. I suspect it is a cavity value rather than a whole wall value. (I understand why a company selling insulation would advertise the value for just the insulation, but it seems like a company selling walls should advertise the value for the wall.) The insulation over the concrete stud is very thin. Based on what I could tell from their web site, the "R-21" version simply adds more insulation in the cavity. If I were building a basement with this system, I would put my money into continuous insulation on the interior as opposed to adding anything more in the cavity.