Why Does Crawl Space Insulation Fall?

Failing Insulation in a Crawl Space BeforeOne common problem we see in crawl spaces time and again is fibreglass insulation that has fallen.

Homeowners often install insulation under the home’s floor joists, inside the crawl space, to improve the home’s heating and cooling efficiency. Whether the insulation was installed professionally or by the homeowner, fallen insulation is most often not due to improper installation; rather it’s a sign of high humidity.

Unsealed crawl spaces are prone to have high humidity. This humidity soaks the fibreglass insulation causing it to become weighted, fall to the ground, rendering it completely ineffective.

Aside from the fallen insulation, how do you know you have a humidity problem in your crawl space?

Inside the home: musty smells, dampness, mould or mildew growth.

Inside the crawl space: Condensation on the plumbing or ductwork, rotting wood and mould or mildew growth.

Failing Insulation in a Crawl Space AfterWhat is the solution for failing and falling insulation?

The solution is to maintain the humidity at an acceptable level by completely sealing the crawl space.

Sealing a crawl space, and thereby regulating humidity levels, involves:

-         Installing a heavy-duty liner on the floor, walls and support columns.

-         Sealing the exterior vents.

-         Removing the wet fibreglass insulation and replacing it with moisture, mould and mildew resistant spray foam insulation, not on the floor system, but on the foundation walls, where outside air meets inside air!

-         In a situation where a home is more prone to excessive humidity, installing a specially designed crawl space sump pump system and an energy efficient and low-maintenance dehumidifier.

If you have fallen insulation, it’s a symptom of a humidity problem. We have a permanent solution to your insulation and crawl space challenge. Please call us to schedule your complimentary inspection and estimate at 1-866-277-1277 or click here to submit your information online.  

About the author

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Ben Bates
Ben Bates lives in the Chatham-Kent area and has been involved in the basement, crawl space and foundation industry since 2008. He has a passion for improving homes the right way and knows what it takes to waterproof, encapsulate or stabilize homes in Ontario. He assists with over 900 projects per year.

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