How To Remove Spray Foam from Surfaces and Skin

Though its most common application is for home insulation, spray foam is one of those miracle products that every DIYer needs to have in their tool arsenal. There are so many uses for spray foam, from filling cracks, to setting fence posts, to securing landscape rocks, that you’ll wonder how you got along without it.

However, if you have to remove spray foam after an errant turn of the wrist, you might think you have a big problem, because it’s extremely sticky stuff. Fortunately, the problem isn’t that big if you act before the foam hardens. We’ll explain what to do.

What Is Spray Foam?

Primarily used as a type of expanding insulation, spray foam is basically a polyurethane product made from isocyanate and polyol resin. In the can, it’s a liquid, but when you spray it and it’s exposed to air, these two chemical compounds react to produce a foam that expands up to 60 times the liquid volume. The foam sticks to pretty much everything, and once expansion is complete and the foam hardens, it’s permanent.

How To Remove Spray Foam

No matter how careful you are, a little bit of spray foam always seems to find its way onto surfaces where it’s not supposed to be. But not to worry: if you’ve created an unintentional sticky mess, clean it up with acetone. A little acetone squirted on fresh foam will dissolve it instantly.

No acetone on hand? Try nail polish remover; that’s the main ingredient in most nail polish removers. The key, however, is to make sure you get to the foam before it hardens.

Here’s how to use acetone to remove spray foam, according to John Parks, a professional insulation installer who regularly works with the stuff:

“The best method is to apply acetone to a clean cloth or rag and gently wipe the area. Never pour it directly onto the surface, especially if you’re near electrical components or working indoors. For tight spots or textured materials, a soft-bristle brush dipped in acetone can help dislodge the foam before it cures. Once it’s hardened, acetone won’t help—at that point, you’ll need mechanical removal, such as scraping or sanding, followed by touch-up work.”

Using acetone safely

Acetone is extremely flammable, so you should not use it around an open flame or other heat sources that could potentially cause a fire. Always keep the lid sealed tightly when you’re not using it, and store it in a cool, well-ventilated space.

How To Remove Dried Spray Foam

If your spray foam mess has dried out, you can start cleaning it up by cutting away as much of it as you can. Just use a putty knife, a saw, or another appropriate cutting tool.

Once the bulk of it is gone, use sandpaper or a hard-bristled brush to remove the rest. Don’t bother using acetone on dried foam. Once the foam has cured, no chemical can soften it.

How to Remove Spray Foam from Your Hands

To start, wear gloves and make sure you don’t have exposed skin when you’re working with spray foam.

Again, acetone is the best option here. Apply some to a clean cloth and wipe the spray foam off your skin. Then, immediately wash yourself with soap and water.

If the spray foam has dried, it’s going to be harder to remove. One method is to use oil and baking soda. Rub oil (cooking oil will work fine) into your hands and then pour baking soda onto them. Rub it all together and let it sit for a few minutes before washing your hands with soap and water.

Another method is to rub the dried spray foam with a pumice stone or an emery board. Gently scrape it, being careful not to remove your skin too. That should loosen up most of it, and then you can wash your hands with soap and water.

If all else fails, the dried spray foam will eventually come off your hands with time.

Use Appropriate Safety Gear

Park has a long list of safety gear that he and his co-workers use when spraying foam insulation. “Based on our professional protocol, here’s what we recommend (and wear ourselves):

• Full-body protective suit with hood – Disposable Tyvek or similar suits prevent skin contact with the foam and keep clothing clean;
• Full-face respirator with organic vapor cartridges – We use respirators that cover the eyes, nose, and mouth to protect from both vapor and overspray;
• Safety goggles or a full-face shield to protect your eyes;
• Headlamp or helmet light;
• Nitrile gloves (disposable or chemical-resistant);
• Long-sleeve coveralls to prevent skin exposure;
• Boot covers or work boots;
• Hearing protection (optional) – On larger commercial jobs, compressors and sprayers can be noisy.”

If you’re doing a small job, such as filling cracks around windows or securing landscape rocks, you don’t need to be as well-prepared as insulation installers. At the very least, however, you should wear gloves, goggles, a respirator and protective clothing. That way, you won’t have to worry about breathing noxious fumes or removing the foam from your skin or clothes.

FAQ

Is spray foam dangerous to skin?

It can be. The isocyanates in uncured spray foam can cause skin irritation and allergic reactions. If you’re exposed to the fumes from foam on your skin, you could develop a sore throat, irritation of the eyes and lungs and even symptoms of asthma, according to the Laborers’ Health and Safety Fund.

How long does it take spray foam to fully cure?

Spray foam becomes stiff minutes after spraying it, but it takes about 24 hours to fully cure, depending on temperature, humidity and the type of foam that you use.

About the Expert

John Parks is the co-owner and COO of San Diego-based Advanced Insulation System. The company specializes in insulation services for commercial and residential properties

Sources

• The Laborers’ Health and Safety Fund: The Dangers of Using Spray Foam Insulation; (2014)