Table 1.
Current insulation levels in existing single-family homes by census division [13] (batt insulation assumed for all).
| NE | MA | SA | ESC | WSC | ENC | WNC | MTN | PA | |
| Ceiling | R-30 | R-30 | R-11 | R-11 | R-11 | R-19 | R-19 | R-19 | R-1 |
| Above-grade wall | R-11 | R-11 | R-6 | R-6 | R-6 | R-11 | R-11 | R-11 | R-6 |
| Floor | R-13 | R-13 | R-3.4 | R-3.4 | R-3.4 | R-11 | R-11 | R-11 | R-5.5 |
Definitions of census divisions: NE (Northeast): MA, ME, NH, VT, RI, CT; MA (Mid-Atlantic): NY, PA, NJ; SA (South-Atlantic): MD, VA, WV, DC, NC, SC, GA, FL; ESC (East-South-Central): AL, MS, KY, TN; WSC (West-South-Central): TX, OK, AR, LA; ENC (East-North-Central): MI, IL, OH, IN, WI; WNC (West-North-Central): MO, IA, MN, SD, ND, NE, KS; MTN (Mountain): ID, MT, NV, AZ, NM, UT, CO, WY; PA (Pacific): CA, OR, WA. Note: The R-value represents the resistance of the insulation to heat flow, with higher values indicating greater resistance. R-values are given in units of °F.ft2.h/BTU.