Insulation and Weatherization Tips
Hints for Staying Comfortable
- Caulk and weather-strip doors and windows that leak air.
- Seal air leaks between your living space and your attic and/or crawl space. Leaks are common around plumbing and vents, heating ducts, light fixtures and wires. Be sure that fixtures and wires are designed for direct insulation contact.
- Install wall plate insulation gaskets behind outlet and switch plates on exterior walls (turn off the power before installing gaskets).
- Install a 6-mil vapor barrier between your living space and your crawl space to prevent moisture from entering your home.
- Make sure your attic and crawl space have adequate ventilation to vent out moisture and summer heat.
Selecting/Installing
- The effectiveness of insulation is noted as an R-value, a measure of the material’s resistance to heat transfer. Higher R-values provide greater insulating value. R-values are additive – the more you add, the higher the R-value will be.
- Use a ruler to check the existing insulation levels in your attic, ceilings, exterior walls, floors and crawl spaces.
Cellulose |
Blown-in Fiberglass |
Fiberglass Batting |
|||
Inches |
R-Value |
Inches |
R-Value |
Inches |
R-Value |
| 5.10 | R-19 | 8.75 | R-19 | 6.00 | R-19 |
| 7.00 | R-26 | 12.00 | R-26 | 7.50 | R-26 |
| 8.10 | R-30 | 13.75 | R-30 | 9.00 | R-30 |
| 10.0 | R-38 | 17.50 | R-38 | 12.00 | R-38 |
- Add new insulation to the existing insulation to increase the R-value using the following guidelines:
House Area |
Standard |
Enhanced |
| Attic/Ceiling | R-38 | R-50 |
| Floor (over unconditioned space) | R-19 | R-30 |
| Wall | R-13 | R-19 |
- Use higher density insulation that has a higher R-value per inch of insulation in cathedral ceiling and in exterior walls.
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