How Much Insulation Do I Need?

Do you need to re-insulate your home? The first obvious question to ask is “how much insulation do I need?” Unfortunately, there isn’t a simple answer.

Let’s start with your current levels of insulation. It’s a good idea to check how much insulation you currently have, which a professional insulation company will be able to help you with. In general, areas checked include:

Behind the walls
The ductwork
Under the floors—including any crawl spaces your home has

How Much to Insulate Your Home

A number of different factors determine how much insulation you need to install:

Age of your home: In general, older homes aren’t usually adequately insulated. If your home was built in the 1970s or earlier, chances are you don’t have enough insulation. Re-insulating can save you a lot of money every year, help make your home more comfortable and help reduce noises from outside as well as between different rooms and levels inside your house.

Where you live: Typically, colder regions like the Northeast need more insulation. According to the North American Insulation Manufacturers Association’s map based on recommendations from the Department of Energy and International Energy Conservation Code, we are in zone 4 here in the tidewater region of Virginia. To give you an idea of insulation R-values for the area, visit ENERGY STAR online.

Type of HVAC system you have: The HVAC system you have is related to how much insulation you’ll need to install. It’s best to talk to professional insulation contractors about your heating and cooling equipment and insulation requirements.

Areas of your home that need insulation: Where you’re insulating will dictate which type of insulation you’ll use and the amount needed. For instance, spray foam has different R-value and thickness requirements than a fiberglass blanket system.

Framing of your home: More heat flows through metal joists and studs than wood ones, so insulating between wall studs or between attic or floor joists doesn’t work as well for houses with metal frames.