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What Happens if Cellulose Insulation Gets Wet?

Cellulose insulation is a loose-fill product made of recycled newspaper treated with chemicals to make it fire-retardant and insect-proof. Humidity has little effect on cellulose insulation, making it a viable option in Southern California’s mildly humid climate.

However, a burst pipe or roof leak may dampen cellulose insulation installed in your attic, exterior walls or crawlspace. When your insulation is inundated with water, you need to act quickly. After all, despite chemical treatments, cellulose fibers aren’t waterproof. Here’s what happens if cellulose insulation gets wet and how to handle it.

Discuss your insulation needs with our experts today by calling (800) 707-9278!

The Effects of Wet Cellulose Insulation

Two things happen when cellulose insulation gets wet:

  • The insulation settles: As a loose-fill product, cellulose relies on its natural fluffiness to fill the space while leaving insulating air pockets between the fibers. Excessive moisture causes the cellulose to sag and settle, an effect that is especially detrimental in wall cavities. Settled insulation could leave the entire upper half of your walls uninsulated!
  • Mold growth sets in: Thanks to its chemical treatment, mold doesn’t grow on cellulose insulation. However, water-soaked fibers sit right against wood studs and drywall, which are susceptible to mold growth. This is why you must act quickly if your cellulose insulation gets wet, since mold can start forming within just a few days.

What to Do with Wet Cellulose Insulation

If you discover wet cellulose insulation in your attic, walls or crawlspace, you have a few options for dealing with the problem:

  • Let the insulation dry out: If only a small area has gotten wet, it may be easy to remove the damp fibers and let them dry for several days before reinstalling them. Even if you must remove most or all of the insulation, it’s sometimes possible to dry out and replace the same fibers—that is, after you thoroughly clean and dry the mold-damaged space.
  • Remove and swap out all the insulation: Sometimes, wet cellulose insulation is not salvageable. In this case, you must remove all the damaged material, completely clean the moldy areas and install new insulation.
  • Repair the leak: Fix whatever caused the cellulose insulation to get wet if you hope to avoid repeating this scenario in the future!

Get Help Cleaning Up Wet Cellulose Insulation

If you think your insulation is wet, please contact OJ Insulation today. We can help you remove the damaged cellulose fibers and help you decide the best way to proceed.

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