PrintWhat Is An R-value?
An R-value is a rating used to measure how well insulation can resist heat flow. The higher the R-value, the greater the insulation properties and the slower heat and cold flows through it. Because insulation with higher R-values is more energy-efficient, the colder the climate, the higher the required R-value.
Different areas of the home have different recommended R-values, depending on what materials are used and how much space is available for insulation. The table below shows the suggested R-values for homes.
The R-value you need will also depend on where you live. The map shows you what R-values you might need, based on your main home heating source.
| Area of Home | Good | Better | Best |
| Attics | R-30 | R-38 | R-49 |
| Cathedral Ceilings | R-19 | R-30 | R-38 |
| 2x4 Walls | R-13 | R-15 | |
| 2x6 Walls | R-19 | R-21 | |
| Floors | R-19 | R-25 | R-30 |
| Crawl Spaces | R-19 | R-25 | R-30 |
| Basement Walls | R-11 | R-13 | R-15 |
*please consult your local building code for the minimum R-value required
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