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Adding New Insulation Over Old or Damaged Insulation

Insulation is vital for your comfort, keeping your utility bills down and protecting your home against pests. Over time, insulation can become waterlogged, blow away or get compacted. When this happens, you need to add on to or replace your insulation. Depending on the situation, our insulation specialists can help you determine which is best for your home.

In this article, we’ll discuss insulation removal techniques and help you determine whether you can add new insulation over your existing insulation.

Do I Have To Remove Old Insulation?

Unless your insulation is wet, moldy or infested with pests, you don’t need to remove it before adding insulation on top of it. ENERGY STAR® recommends that you inspect your insulation for signs of mold, mildew, moisture and pest infiltration before making this determination.

If you discover these problems, you should locate and correct the problem. If it’s not addressed, you could risk damaging your ceilings or rafters. Once corrected, you can remove any damaged insulation and then add your new insulation on top.

How Should I Replace My Old Insulation?

This depends on what type of insulation you have in your attic/walls, where it’s located and whether the insulation is damaged. If your insulation is wet or damaged, we strongly recommend replacing it before applying a new layer. Otherwise, the problem will spread throughout the new insulation and could significantly damage roofing structures.

If the insulation is in good condition, then a new layer can be placed on top without difficulty. However, the application method depends on the type of insulation already in place.

For instance, batt, rolled insulation and blown loose-fill fiberglass or cellulose insulation are easily installed over old insulation. It’s simply laid down or blown over the existing insulation and will create a seamless transition between layers. However, with batt insulation, it’s advisable to use unfaced rolls that are laid out perpendicular to the joists.

When choosing rolled insulation, it shouldn’t be tacked down. This is because the tacking process can squash or flatten the insulation and diminish its R-value.

If you have vermiculite insulation in your attic, this should be tested for the presence of harmful chemicals and toxins, including asbestos. If chemicals, toxins or asbestos are found, you’ll want to have it thoroughly removed by a certified professional before installing new insulation.

Finally, we strongly recommend that you air seal your attic before adding any new insulation. Air sealing will eliminate air leaks that can diminish the performance of your insulation and significantly reduce your home’s energy efficiency and overall comfort.

Make sure you work with an experienced insulation contractor to remove or replace your insulation. A professional can make sure the job is done safely and correctly.

Why You Should Hire a Professional

It’s just insulation. How hard can it be to install? You’ve probably seen plenty of YouTube videos that make it seem easy to inspect, add and replace insulation. While it’s true that some steps are simple, many details need to be accounted for throughout the process.

Hiring a certified insulation specialist ensures the job is done right, that all details are properly addressed and that any problems are effectively resolved. Yes, it costs more to hire an insulation professional, but the enhanced comfort and energy savings it generates year after year more than offset the cost.

Call a Professional Insulation Company in California

The insulation contractors at OJ Insulation are dedicated professionals with the required training and certifications to effectively apply residential insulation and commercial insulation in California.

As a proud member of the IBP Family of Companies, we work hard to offer superior service and reliable solutions to your needs. Our thorough knowledge of California building codes, coupled with our expert knowledge of insulation technologies and installation techniques, allows us to deliver superior quality.

When you want solutions you can depend on, you can always count on our team to give you our very best.

Contact OJ Insulation at (800) 707-9278 to learn more about our company and schedule an inspection of your property today.

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