How Much Insulation Do I Need in My Attic?

A frequent question for homeowners is, ‟How much attic insulation do I need?” One reason this is so commonly asked is that the answer changes depending on where you live and when your home was built. Different climates require different types and amounts of insulation. Plus, most homes built before 2007 are under-insulated by today’s standards. Due to the rising costs of energy, even homes built in 2014 have more attic insulation than those built just four years earlier. Here’s a quick checklist to clear up any confusion on the amount of attic insulation your home needs.

How much insulation do you have now? The first step to answering the question, “How much insulation do I need,” is to measure your current insulation, if any. Use a ruler to figure out the depth of the insulation in inches. Measure from the floor to the top of the fill. If your attic is currently uninsulated, you will likely need a higher R-Value (Resistance-Value) to make sure your home is properly insulated.

What temperate zone do you live in? Next, take a look at the ENERGY STAR map 1 in Fig. 1. Locate your zone and then proceed to the corresponding number in the checklist below. Minimum and recommended insulation amounts vary from state to state, and even county to county. If you want a customized reading, the United States Department of Energy provides this ‟how much insulation do I need calculator.” Additionally, all of the specific Residential Prescriptive Requirements for your county and state can be found on the government’s Energy Codes website.

How much insulation in attic for Zones 1-4? In Zone 1, the average minimum requirement for attic insulation is 9 inches of R30 fill. The average recommended level is 14 inches of R49. In Zone 2, the average minimum requirement for attic insulation is 9 inches of R30 fill. The average recommended level is 17 inches of R60. In Zone 3, the average minimum requirement for attic insulation is 9 inches of R30 fill. The average recommended level is 17 inches of R60. In Zone 4, the average minimum requirement for attic insulation is 11 inches of R38 fill. The average recommended level is 17 inches of R60.

How much insulation in attic for Zones 5-7? In Zone 5, the average minimum requirement for attic insulation is 11 inches of R38 fill. The average recommended level is 17 inches of R60. In Zone 6, the average minimum requirement for attic insulation is 14 inches of R49 fill. The average recommended level is 17 inches of R60. In Zone 7, the average minimum requirement for attic insulation is 14 inches of R49 fill. The average recommended level is 17 inches of R60.

As mentioned, please check your local codes and requirements before attempting anything on your own, or simply call Terminix® for a free insulation inspection. Not only will you learn how much insulation in attics is needed, but also how your new insulation can be working to keep pests out of your home.