Most insulation lasts 15 to 100+ years depending on the type, but you should replace it sooner if you notice temperature changes, rising energy bills, or pest damage. How often you replace insulation depends on the material: cellulose degrades after 15–30 years, fiberglass can last 80–100 years, and spray foam can exceed 100 years unless compromised.
Insulation is an important part of your home, keeping you safe and comfortable no matter the weather outside. Although most people understand this importance and install insulation as soon as possible, they often don’t know how long house insulation lasts or when to schedule a replacement.
Below, we’ll walk you through the factors that determine how often insulation needs to be replaced and the warning signs that mean it’s time to act sooner.
What Type of Insulation Do You Have?
How often you need to replace your insulation will depend on the insulation type. Cellulose insulation, often a supplementary form of insulation, has the shortest lifespan. It starts to degrade after 15-30 years. Since it’s supplemental, you may discover that it aged the main form of insulation, even if that form typically lasts longer. Another supplemental form of insulation is mineral wool, which has a longer lifespan of 30-80 years depending on the base of the wool itself.
Fiberglass and spray foam are the two longest-lasting forms of insulation. Fiberglass can easily last for 80-100 years unless it comes loose from its batts, which can start to happen after the first decade.
However, most insulation contractors no longer use batts due to this problem. Spray foam insulation can last well past 100 years unless compromised by outside forces such as inclement weather, construction, or pests.
Understanding how long house insulation lasts for each material type helps you plan for future maintenance and avoid unexpected replacements.
Are You Noticing Indoor Temperature Changes?
If you’ve been in your home a long time, you know exactly how to set your thermostat for your comfort. You probably use a temperature range for the cooler and warmer days through each season. If you notice that you need to change these temperatures more often, or that you’re still too hot or too cold regardless of the reading on the thermostat, something may be wrong with your insulation.
It may be time for a replacement, even if it seems sooner than the typical timeline for how often you should replace insulation.
Are You Using More Energy?
Maybe your home is staying at the same temperature but your energy bill has skyrocketed. This could be because your HVAC system is compensating for degraded or damaged insulation, so it needs to heat or cool more to keep you at a comfortable temperature.
Arrange for a professional home energy audit, since these professionals can use advanced tools to see if the problem is with your insulation or in other faults, such as drafty windows. If they confirm that the problem is your insulation, then it’s time for repairs or a replacement.
Have You Seen Any Pests Recently?
As we mentioned above, pests are one of the only things that can cause spray foam insulation to need replacement. If that’s the type of insulation you have, be on the lookout. While it’s natural for critters to try to dig into your ceilings and walls during colder months, they shouldn’t be successful if your insulation is good.
If you see pests somewhere inside the house, that means you have compromised insulation and should replace it immediately. You must call a professional exterminator and insulation contractor.
How long does house insulation last before it needs to be replaced?
House insulation lasts anywhere from 15 to 100+ years depending on the type. Cellulose insulation needs to be replaced after 15–30 years, mineral wool lasts 30–80 years, fiberglass can last 80–100 years, and spray foam insulation can exceed 100 years.
However, how often insulation needs to be replaced also depends on whether it’s been damaged by moisture, pests, or settling. If you’re noticing temperature fluctuations, rising energy bills, or pest activity, your insulation may need to be replaced sooner than expected.
How often should you replace insulation?
Either after the typical lifespan of your insulation or if you notice problems such as temperature changes, high energy usage, and pests. Keep an eye out for these signs and contact our professional insulation contractors to fix or replace insulation if any of these problems arise. We’re happy to help keep your home safe and comfortable.