Wow! Its cold outside today! Randy and John just got back from the national ASHI convention in New Orleans and were not to pleased to come back to the snow! Not that it was much warmer in New Orleans – mid 30’s for the 1st weekend of Mardi Gras.
The cold weather is a good time to talk about insulation in houses. The International Residential Code (IRC) 2006 defines the Kansas City area to be in Climate Zone 4. This means that the requirement for attic insulation in buildings that are being constructed to current standards is R-38. This is the MINIMUM standard for energy efficiency in a home.
There are various types of insulation, and each insulation has a different R-value / inch. But generally speaking, the R-value for blown-in cellulose is roughly 3.7 / inch. And the R-value for fiberglass batt insulation is 3.14 / inch. Both types of insulation are very common in the greater Kansas City area. This means that the blown-in cellulose should be at least 10-11 inches deep. Fiberglass batt insulation should be at least 12 inches deep.
For the most part, more insulation means better energy efficiency. If you look inside your attic and see the tops of the rafters, you don’t have enough insulation! Meeting or exceeding these standards can cut your utility costs significantly and can make your home a more attractive investment for someone looking to buy.
A good calculator for R-values can be found at the ColoradoENERGY website.