How Often Should Attic Insulation Be Replaced

Most homeowners understand that they’ll need to replace their insulation at some point. As with every other part of the home, the insulation in your home is going to break down, and going through the replacement process is inevitable. Figuring out when to replace your insulation, though, is the tough part.

The truth is that there’s no definitive moment at which insulation needs to be replaced. Instead, you’ll have to look at the balance of a number of factors to figure out when the replacement needs to be done. Before you start looking at replacements, you’ll need to look at a few major issues, including:

  • Insulation type
  • The condition of your home
  • The appearance of leaks

Factors that Affect When You Will Replace Your Insulation

Type of Insulation

One of the biggest factors you are going to deal with is the type of insulation in your home. As you might imagine, every type of insulation is different so it degrades at different speeds. Below is a rough estimate of when you’ll need to start thinking about replacing each type of insulation.

Insulation Batts

The big thing you’re going to look for here is whether or not the fiberglass is falling from your batting. If the fiberglass isn’t starting to fall, you’re in luck – your batting could be in great shape for many years to come. As a rule, though, you’re going to start looking at replacing your batting after about fifteen years in ideal circumstances.

Blown-in Insulation

While blown-in insulation can actually do a great job of keeping your home well-insulated, it’s also a form of insulation that degrades a bit faster than its counterparts. Your goal is to take a look at what you’ve got and to see its general condition. If it is starting to crumble or fall apart, you’re witnessing the degradation of the cellulose in this type of insulation.

You should generally expect to see this form of insulation start to degrade in about fifteen years. Most of the insulation starts to go in twenty to thirty years, so any home that was built before the turn of the millennium likely needs to have its insulation checked at this point.

Spray Foam Insulation

The great news about spray foam is that it can literally last a lifetime. In fact, most people who have spray foam insulation will never have to worry about replacing the installation in their homes. Instead of looking for degradation, you’re going to look for external problems – holes caused by weather or vermin, for example, or other issues that cause your spray foam insulation to be compromised.

Unstable Temperatures

Insulation works by reducing the heat transfer between the interior and exterior of your home. In short, it prevents cold or heat from outside from moving inside, helping to keep your home at an even temperature. If you are experiencing unstable temperatures, then, there’s a good chance that your insulation needs to be replaced.

Unstable temperatures generally occur when a portion of your insulation is no longer preventing heat transfer. This may be due to the fact that your insulation is starting to fall apart, but it also might be a sign that you never had adequate insulation in the first place. If you can’t keep your home’s temperature from fluctuating, you need to check out your insulation as soon as possible.


Your final step should be to look at the condition of your home. Leaks and holes in your home can both make it harder for your insulation to regulate heat transfer and for your insulation to stay in one piece. If you have leaks or drafts, you need to fix them as soon as possible.

Your goal should be to start out by looking at the obvious places. Replacing some shingles that were blown away by a storm can help, as can patching drywall inside your home. Look for things like loose exterior boards, holes in the ceiling, and even significant structural damage in and around your floors to find out where the problem lies. If you see a hole near your insulation, be aware that you’ll need to check out your insulation for weather damage to determine if it needs to be replaced.