How Often Should You Replace Your Attic Insulation

You change your air filter every three months, and your car's oil every 5000 miles... but how often should you replace your attic insulation? Here is what you need to know.

When the current insulation in your house begins to deteriorate, trouble is sure to follow. A home that uncontrollably lets in warm outdoor air and lets out your cool air, high energy bills, and health risks are only some of the issues you can face. 

Knowing when to anticipate the deterioration of your attic insulation is essential. So how often should attic insulation be replaced? The existing insulation in your attic won't keep its protective properties forever. After a period of around 15 years, homeowners should seriously consider getting an audit done on their home insulation.

Let's examine the common types of insulation in your home and discuss the variables that might cause your home's insulation to deteriorate as well as telltale indicators that something is amiss.

What Type of Insulation Do You Have? 

Blown-In Insulation (Fiberglass And Cellulose)

Because it is both efficient and economical, blown-in or loose-fill fiberglass is an insulation material that sees widespread use. In most homes, loose-fill insulation can survive anywhere from 80 to 100 years before needing replacement, provided that it is not damaged. If the insulation installed by contractors is more than 15 to 20 years old, it might be time for a home energy audit or an inspection by certified home inspectors or attic specialists. Blown-in fiberglass insulation may settle and sag after more than a decade. 

Cellulose is good at preventing air leaks and is more eco-friendly than certain other forms of insulation. Cellulose has even been demonstrated in specific experiments to prevent fires from spreading through a house.

On the other hand, cellulose insulation does not hold up as well over time since it is mainly composed of recycled materials. The typical lifespan is between 20 and 30 years, with degeneration starting as soon as 15 years following installation.

The life expectancy may be shortened by harsh weather or intervention from the outside, just as it can with other forms of insulation.

You often use cellulose as supplemental insulation. Therefore, even if most of the insulation in your house is made of different materials, the presence of cellulose means that you may begin to experience a negative impact as cellulose deteriorates.

Spray Foam Insulation

Spray foam is one of the most long-lasting and effective attic insulation options. It may endure an extended period, perhaps even a century or more. Because spray foam insulation is mold resistant and doesn't retain water, it tends to remain in place until manually removed.

Spray foam insulation is a popular option among Dallas homeowners since it lasts for many years without replacing it. However, if your spray foam insulation has damage due to bad weather, rodents, construction, or other circumstances, it may be time to replace it with new insulation or repair it.

Batt Insulation

Blown-in insulation is best for floors, but you usually use fiberglass batts for the walls. Batts are easy to put in yourself and are cost-effective. After 15 to 20 years, insulation can start to fall off of fiberglass batts.

Foam Board Insulation

Foam board is an excellent alternative to the typical fiberglass batt insulation. It offers a high R-value per inch, is moisture-resistant, and is simple to work with. Foam board is a good option anywhere it can get wet such as an outside foundation and within a basement against the foundation. Foam board is more costly than fiberglass batts, so use it when moisture is an issue and if your budget allows.

Foam board lasts 100 years or more due to its stiffness and water resistance. As with any others, the product's longevity depends on proper insulation installation and damage. 

Rock Wool Insulation

Similar to fiberglass, rock wool comes in easy-to-install batts. Manufacturers create rock wool from rocks, which seems impossible at first.

Homeowners may use rock wool in walls, floors, ceilings, attics, and crawl spaces. It's best for rooms on the chilly northern side of the house and soundproofing movie rooms or music studios.

Rock wool or mineral wool insulation may last 30 to 80 years, depending on the quality of installation.

Rock wool is prone to mold and mildew growth. Certified attic specialists need to replace attic insulation if it becomes wet, even if it's brand new.

Radiant Barrier Insulation

Using a radiant barrier in the attic reduces summer heat gain and cooling bills by reflecting sun rays. Manufacturers build radiant barriers with an aluminum sheet thin enough to reflect 97% of the heat that touches the material to keep the heat from passing through. As long as certified attic specialists install them appropriately, radiant barriers may endure for 80 to 100 years. It's a long-term investment that doesn't have any major drawbacks.

What Does The Insulation Look Like?

Replace any wet insulation or insulation with mold growth upon discovery. For example, due to leakage, old varieties of fiberglass insulation may get wet, causing it to collapse and "flatten," which greatly diminishes its effectiveness. If this occurs in the winter, you're in for an expensive time attempting to supply your home with conditioned warm air. Even if you can easily replace your insulation, you run the risk of having the same problem recurring if it is ever exposed to moisture again.

What Is the Temperature In Your House?

If you move into a new house, there are clues if it's poorly insulated. It may be unreasonably chilly or hot, and you might see heating and cooling costs soar.

Poor attic insulation may be to blame if your heating and cooling are on, yet some rooms seem to be filled with cold air while others are sweltering. If one area is noticeably allowing cold air than the others, you may want to investigate if attic insulation is causing the uneven temperatures. 

How Is The Air Quality In Your Home?

If you observe yourself or family members suffering from unexplained respiratory illness or are generally uncomfortable in the house, you may have improperly installed insulation or insulation that has lost its sealing power. 

To maintain and improve indoor air quality, you need to eliminate the allergens, dust, and pollutants that enter your home via cracks and other air transfer sites. 

Additionally, you enhance indoor air quality and peace of mind when you prevent and control mold and mildew growth by reducing the amount of air and water vapor entering your house. A properly installed and maintained insulation functions as a protective seal and keeps unwanted particles and water vapor out. Ensure that the air quality in the place you live remains satisfactory by inspecting and replacing old insulation.


Attic insulation can last 80 to 100 years, though it loses its energy efficiency benefits with time. Certified attic specialists' professional advice is to upgrade it every 15 years to ensure that it is still performing the job. Whenever you have a roof leak, check to see if it has water damage and repair it if required.

Installing and maintaining attic insulation is beneficial in making homes energy efficient and comfortable. When the attic insulation is in excellent shape, the HVAC system does not have to work as hard, saving you money by avoiding repairs or insulation replacement.

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