Does your home always seem to be drafty and hard to keep comfortable? If it’s more than a decade or two old, there’s a good chance that it’s under-insulated, which can mean significantly higher heating costs in the winter and cooling costs in the summer.
But how much insulation do you need? Recommended insulation levels vary by region, with higher R-values needed for colder climates.
What Does Insulation R-Value Mean?
An insulation’s R-value describes its resistance to the flow of heat. A material with a lower R-value will let more heat bleed through faster than an insulation with a higher R-value.
The goal is to slow down the amount of heat transferred through the insulation to keep your home warmer in winter and cooler in summer. This reduces the work your HVAC system has to do to keep your home comfortable and lowers your energy costs.
How Is Insulation R-Value Calculated?
An R-value reflects resistance to heat loss across an insulating material over a given period of time. Different materials can be compared by calculating their R-value per inch. Wood has an R-value of 1, so a 3-inch board would be rated at R-3.
Spray foam insulation with a rating of R-5 per inch would have a total R-value of R-15 when installed at a 3-inch thickness. Fiberglass batts rated at R-3.7 per inch would have a total value of R-11.1 at a 3-inch thickness.
What Are Recommended R-Values for the Washington, DC Metro Area?
Maryland and the Washington, DC, area are in Climate Zone 4, so the insulation levels recommended by the U.S. Department of Energy are as follows for common areas of the home:
- Attic: R-60
- 2×4 walls: R-13 in the wall, plus R-10 of continuous insulation on the exterior
- 2×6 walls: R-20 in the wall, plus R-5 of continuous insulation on the exterior
- Floors and crawl spaces: R-19 to R-30
In many cases, more insulation can be added over the top of existing insulation to bring your home up to the recommended levels.
R-value can change over time, as well. Blown-in cellulose or fiberglass can settle, losing some of its R-value, and fiberglass batts will also decrease if they’re compressed.
Source: energystar.gov
Contact Accurate Insulation for Home Insulation Services in DC & Maryland
When you’re ready to upgrade the insulation in your DC home, contact Accurate Insulation. We offer professional insulation installation in Maryland, Northern Virginia, and the Washington, DC, area, and we feature many great reviews from our customers in these areas.
We provide superior service at competitive rates, with next-day service available for most jobs. We believe in honesty, integrity and excellent service, and your complete satisfaction is our goal. We’re fully licensed and insured, and we feature top-quality insulation products that include spray foam, fiberglass, cellulose, vinyl, rigid foam and more.
For expert insulation services from the leading insulation contractor in DC and Maryland, call Accurate Insulation today at 301-358-6411 or contact us online.
