What, if any, is the "R-value" of a 10" concrete wall. I want my basement walls to have an effective R-19 value, so how much insulation do I need to add to the interior?
Concrete has an R-value of about 0.20 per inch of thickness, so your wall would have an R-value of approximately 2.0. Basically you will need to add the full R-19 value to the interior.
Architect (NY) and Home Designer (PA)
Posts: 2492 | Location: Tobyhanna, PA | Registered: 24 October 2005
Thanks for the info, Richard. Second question: part of my basement is framed using 2X12 studs which effectively gives me approximately 2" on the concrete walls for insulation. Is there any type of insulation that I could install in that space which would give me the R-19 rating that I am looking for? Thanks!
Foam insulating boards have an R rating of about R-5 per inch of thickness...this may vary slightly depending on the particular foam...so R-10 is what you'd have if you filled the 2" space with foam.
I don't know of any type of insulation that would give R-19 in 2 inches.
Architect (NY) and Home Designer (PA)
Posts: 2492 | Location: Tobyhanna, PA | Registered: 24 October 2005
QUESTION: ARE THE BASEMENT WALLS EXPOSED OR ARE THEY BURIED BELOW GROUND?
IF THEY ARE BURIED, USUALLY PERIMETER INSULATION IS REQUIRED IN THE R-5 TO R-8 RANGE FROM GRADE DOWN A MIN. 48". OR IF THEY ARE EXPOSED, ANY THICKNESS "EXTERIOR FOAM INSULATION SYSTEM" (DRYVIT OR EQUAL) CAN BE APPLIED TO THE EXTERIOR SURFACE INCREASING THE "R VALUE". ALSO TRY "ASTROFOIL", A MYLAR BASED REFLECTIVE QUILTED VAPOR BARRIER PLACED DIRECTLY BEHIND THE DRYWALL RATHER THAN THE STANDARD 6 MIL. POLYETHYLENE WILL INCREASE THE "R VALUE" BY APPROX. 4 TO 7 POINTS.
