When it’s time to add more insulation to your home, the attic is usually the primary destination. During winter, heat rising inside your house accumulates at the ceiling. Heat loss by conduction, that raises operating costs, is directly affected by the amount of attic insulation. In summer, the situation reverses as acute attic heat radiates down into living spaces. Deciding when to add more insulation and how much depends on existing levels. If your house is over 10 years old and still has the original attic insulation installed at construction, it’s probably under-insulated by today’s stricter energy conservation standards. Here’s how to tell if it’s time to add more insulation to the attic:
An at-a-glance visual assessment can give you a rough idea of the status quo. Look across the span of attic floor joists. If insulation between the joists is below or only even with the top of the joists, you probably need more. The level of insulation should completely fill the space between the joists as well as mound up above, exceeding the tops of the joists. Also, there should be no spots where insulation thins out noticeably such as the edges of the attic at the eaves.
A more accurate evaluation can be made by measuring attic insulation. The Department of Energy sets insulation standards for climate zones based on the insulation’s R-value per inch. In Amarillo’s climate zone, the DOE recommends attic insulation depths ranging from R38 to R60. For conventional fiberglass batts—usually the easiest DIY upgrade to make in an attic—that R-value translates to 12 inches to 18 inches. For loose-fill cellulose that’s injected into the attic through hoses under air pressure, the proper range is 10 inches to 16 inches.
Before upgrading attic insulation, make sure to seal air leaks between the living spaces and attic. Attic insulation won’t do much to stop leaking air—another major source of heat loss—but it may conceal the location of leaks and make them harder to find.
For help with your heating and cooling needs contact the professionals at Amarillo Air Conditioning.
Our goal is to help educate our customers in Amarillo, Texas about energy and home comfort issues (specific to HVAC systems). For more information about insulation and other HVAC topics, download our free Home Comfort Resource guide.
Credit/Copyright Attribution: “John Kasawa/Shutterstock”