The Blog

What Happens When Your Insulation Gets Wet

By Mike on April 14, 2015

There are many ways that water can gain access to your crawl space. Holes and cracks can let moisture in through the walls, foundation, and corners of the crawl space. Flooding or a burst water pipe can also result in excess water that will then be absorbed by the insulation.

Wet insulation is insulation that can no longer perform effectively. Knowing what kind of insulation you have and how to handle it is a critical part of protecting and caring for your home.

Here are 3 of the most common types of insulation and how they respond to increased water and moisture levels in your crawl space.


What Happens When Fiberglass Insulation Gets Wet?

Fiberglass insulation is commonly found either in large segments that are rolled out or in the form of blown-in insulation. This type of insulation is made out of spun sand and recycled glass, which is then held together by a binder to form sheets or pellets.

The way that fiberglass insulation works is by trapping little pockets of air inside the insulation so that it cannot disseminate through the wall. However, when these pockets become filled with water, the fiberglass can no longer insulate effectively.

Drying out fiberglass is not always possible or successful. Once fiberglass gets wet, it tends to compact and lose its insulating abilities. In addition, wet fiberglass is an ideal breeding ground for mold and animals.

What To Do About Wet Insulation:

Fiberglass insulation that is anywhere between mildly moist and dripping wet should undergo a thorough inspection. A crawl space insulation contractor can help to analyze the damage and propose possible solutions. In most cases, the damaged insulation will not be salvageable. Have it removed to protect your crawl space from mold and mildew, seal the crawl space from further water damage, and then have your crawl space reinsulated.

What Happens When Foam Board Insulation Gets Wet?

Polystyrene, usually known as foam board insulation, is a popular type insulation in Seattle, Everett, and the surrounding areas. Foam board insulation sheets are used during the initial construction of the home. It is usually added in the wall cavities and crawl spaces. Polystyrene insulation consists of tiny polystyrene beads, which are compressed together to form large boards that can be cut and resized, which makes it easy to fit to specific or oddly shaped areas.

Foam board insulation is fairly good at resisting water damage, but it has other drawbacks. Large sections of foam board can make it difficult for any accumulated moisture between the wall and the insulation to escape. This residual moisture collects against the wall, causing bacteria and mold growth, and even wood rot. If not quickly addressed, this can become an enormous (and expensive) problem.

What To Do About Wet Insulation:

If moisture is found to have accumulated behind or around your crawl space foam boards, removing the foam boards and drying out the space should be a top priority. It may also be time to consider alternative insulation options. Since crawl space conditions can be hard to predict, the continued use of foam boards may only mean more trouble for your crawlspace in the future.

What Happens when Spray Foam Insulation Gets Wet:

Spray foam insulation has been developed from two composite materials, polyurethane and isocyanate. This powerful insulation can be produced in a open-cell or closed-cell fashion, each with their own list of benefits. Closed cell spray foam insulation works as an incredible vapor barrier and has the highest resistance value on the market.

Closed-cell spray foam insulation is completely waterproof and moisture resistant. In addition, the chemical makeup of the material leaves no food value for bacteria or mold to grow.

What To Do About Wet Insulation:

What should you do when your spray foam insulation is wet? Lucky for you, very little! Spray foam insulation’s ability to resist water keeps it from being a threat to the structural integrity of your crawl space. If, however, you have standing water in your home, it is likely that water will have seeped beneath the spray foam insulation. In such cases, one of our crawl space consultants should be consulted.

If you’ve discovered wet insulation in your crawl space, your home could be at risk. At Clean Crawls, we specialize in crawl space cleanout, insulation, and restoration. Our team of crawl space consultants would love to help you get your crawl space in top condition so that you can start enjoying the benefits. For more information, give us a call or fill out our contact form.


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