The Department of Energy (DOE) recently released its new R-value recommendations for new and existing homes. The insulation recommendations for attics, cathedral ceilings, walls and floors have been increased overall and generally exceed those required by most building codes.
New Wood-Framed Houses
Zone | Heating System | Attic | Cathedral Ceiling |
1 | Gas, Oil, Heat Pump, Electric Furnace | R30 to R49 | R22 to R38 |
2 | Gas, Oil, Heat Pump, Electric Furnace | R30 to R49 | R22 to R38 |
3 | Gas, Oil, Heat Pump, Electric Furnace | R30 to R49 | R22 to R38 |
4 | Gas, Oil, Heat Pump, Electric Furnace | R38 to R60 | R30 to R38 |
5 | Gas, Oil, Heat Pump, Electric Furnace | R38 to R60 | R30 to R38 |
6 | Gas, Oil, Heat Pump, Electric Furnace | R49 to R60 | R30 to R60 |
7 | Gas, Oil, Heat Pump, Electric Furnace | R49 to R60 | R30 to R60 |
8 | Gas, Oil, Heat Pump, Electric Furnace | R49 to R60 | R30 to R60 |
Existing Wood-Framed Houses
Zone | Uninsulated Attic | Existing 3-4 Inches of Insulation |
1 | R30 to R49 | R25 to R30 |
2 | R30 to R49 | R25 to R38 |
3 | R30 to R49 | R25 to R38 |
4 | R38 to R60 | R38 to R60 |
5-8 | R49 to R60 | R38 to R49 |
The Following Chart is a list of R-Values for common types of insulation. Take a measurement of your current inches and multiply the inches by the following number that matches your current type of insulation.
Blown Pink or Yellow Fiberglass | 2.2 |
Blown White Fiberglass | 2.8 |
Blown Rockwool | 2.8 |
Blown Cellulose | 3.7 |
Batt Fiberglass | 3.1 |
So for example if you measure 4 inches of pink fiberglass your would take 4" X 2.2 and you would have about an R9 insulation R-Value.