Cost-effective Insulation R-Values for Existing Homesa
If you live in a climate that is...
and your heating system is…b
insulate to these levels in the…
ceiling
wood-frame wall
floor
basement/ crawl space wallsd
Warm with cooling and minimal heating requirements (i.e., FL & HI; coastal CA; southeast TX; southern LA, AR, MS, AL & GA).

gas/oil or heat pump

electric resistance

R-22 to R-38

R-38 to R-49

R-11 to R-13

R-13 to R-25

R-11 to R-13

R-13 to R-19

R-11 to R-19

R-11 to R-19

Mixed with moderate heating and cooling requirements (i.e., VA, WV, KY, MO, NE, OK, OR, WA & ID; southern IN, KS, NM & AZ; northern LA, AR, MS, AL & GA; inland CA & western NV).

gas/oil or heat pump

electric resistance

R-38

 

R-49

R-11 to R-22c

R-11 to R-26c

R-13 TO R-25

R-25

R-11 to R-19

R-11 to R-19

Cold (i.e., PA, NY, New England, northern Midwest, Great Lakes area, mountainous area (e.g., CO, WV, UT, etc.)).

gas/oil

heat pump or electric resistance

R-38 to R-49

R-49

R-11 to R-22c

R-11 to R-28c

R-25

R-25

R-11 to R-19

R-13 to R-19

a. Adapted from the U.S. Department of Energy 1997 Insulation Fact Sheet.
b. Insulation is also effective at reducing cooling bills. These levels assume your house has electric air-conditioning.
c. R-values may be achieved through a combination of cavity insulation and rigid board insulation and are for insulation only (not whole wall).
d. Do not insulation crawl space walls if crawl space is wet or ventilated with outdoor air.