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Should I install radiant barrier insulation even if I already have attic insulation?

If you have enough thermal insulation in your attic—cellulose and/or fiberglass insulation installed in the flooring, knee walls, etc.—that’s great. Your home is more energy-efficient than many other homes. But you may need radiant barrier insulation too.

The attic is one of the biggest sources of energy loss in homes and is, therefore, one of the best places to insulate. In warm climates like here in Southern California, the best attic insulation—and most cost-effective solution—is a combination of thermal insulation and a radiant barrier. So even if you have enough cellulose and/or fiberglass insulation, you may still need radiant barrier insulation, which works differently than thermal materials.

Radiant Barrier vs. Blown-In Insulation

Radiant barrier is made of foil and is typically installed in attics, right underneath the roof. It helps your home reflect, rather than absorb, heat from the sun, which keeps your home a lot cooler and more comfortable, especially in the summer. In fact, homes with radiant barrier insulation are up to 10 degrees cooler than homes with no attic insulation—this makes a huge difference with our warm temperatures here in Southern California!

When it comes to attic insulation, you shouldn’t think of it as radiant barrier vs. blown-in insulation (fiberglass and cellulose) and which one would be better. Instead, a combination of the two is most likely the most cost-effective—you’ll have to talk to an insulation company for specifics, though.

Radiant barrier is especially beneficial if:

  • Your attic has air ducts
  • You have an asphalt roof (which absorbs heat more easily than other types of roofing, such as metal)
  • Your home gets little or no shade from trees

Do You Need More Attic Insulation?

Unsure if you have enough attic insulation? Although insulation professionals will be able to tell you for sure, there are a few signs you can look out for on your own that could indicate you need more insulation:

  • Energy bills that are higher than normal (check your bills for the same time of year last year)
  • The second story of your home is uncomfortably warm
  • Your air conditioner is running more in the summer
  • Snow melts off your roof too quickly and/or ice dams form in the winter

To learn more about radiant barrier insulation and other attic insulation, or if you need to install more insulation in your home, contact OJ Insulation today!

Where should you insulate in your home? Check out our interactive infographic:

Home Insulation

We insulate attics, walls and crawl spaces.

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