How Soon Can You Go Home After Spray Foam Is Installed?

You’re considering spray foam insulation, but you heard you must vacate your home while it’s sprayed. Not only is this inconvenient, it is unlike any other insulation product you’ve heard of. Is it true that you have to vacate? If so, how long until it’s safe to go home again?

South Central Services has installed spray foam insulation for hundreds of projects in and around southern Pennsylvania. The safety of our crew and clients is our highest priority. We are happy to share why you have to vacate and how long it will take to go home safely.

By the end of this article, you will know:

• Why homeowners must vacate when spray foam is installed
• What off-gassing is and how it works
• How long it takes for spray foam insulation to cure

Don't have time to read right now? Check out everything you need to know at a glance.

Why Do I Have To Vacate While Spray Foam Is Installed?

One of the many factors that makes spray foam unique is its manufacturing process. Most insulation products are manufactured and sold for installation. Spray foam is not manufactured before being sold for installation. Instead, contractors purchase manufactured components that create spray foam. Then, spray foam is manufactured and installed simultaneously at the job location.

During manufacturing, spray foam produces off-gassing. Off-gassing is a byproduct of the chemical reaction that creates spray foam. Off-gassing is a normal byproduct, but it is toxic to inhale. The off-gassing byproduct is why contractors wear respirators while applying spray foam. Residents and pets are required to vacate the premises for their safety.

Is Off-Gassing Dangerous?

Off-gassing is not a phenomenon limited to spray foam manufacturing. Many products that we use every day off-gas some amount of toxic fumes during manufacturing. The smells from a new car, pair of shoes, and mattress are all examples.

Those odors eventually fade because the chemical reaction that created the product is finished. Once the chemical reaction is complete, no more byproducts like off-gassing can be made.

Regardless of how common off-gassing is, inhaling toxic fumes is never a recommendation.

How Much Does Spray Foam Off-Gas?

When installed correctly, spray foam insulation will off-gas in proportion to how much foam was installed. Off-gassing can only occur as a result of a chemical reaction. Once a chemical reaction is complete, additional byproducts cannot be generated.

If installed incorrectly, spray foam insulation could off-gas indefinitely. This off-gassing is related to off-ratio foam, where some amount of a chemical is left behind and tries to react. The chemical reaction is not complete if the foam is off-ratio.

Below is a diagram explaining the ratios, products, and byproducts of the spray foam chemical reaction.

Chemicals react in a 1:1 ratio to create spray foam insulation. All of the chemicals are used up in the reaction. What remains is the finished product of spray foam and the byproducts of off-gassing fumes and heat.

Both the heat and the off-gassing fumes will dissipate while the foam cures.

How Does Spray Foam Cure?

The chemical reaction that creates spray foam is an exothermic reaction, which means it produces heat. Heat is the critical component that cures the foam. Spray foam is warm to the touch immediately after spraying because of the exothermic reaction. After the reaction has occurred, the foam starts to cool.

Spray foam is considered cured after cooling completely to room temperature. This cooling and curing process is finished after twelve to twenty-four hours.

So, When Can I Go Home After Spray Foam Installation?

After curing, spray foam is a safe and inert product that is safe to live surrounded by. All off-gassing fumes will have dissipated or been ventilated out of the home after curing.

So, twelve to twenty-four hours after spray foam insulation is installed, you should be able to return home.

The Bottom Line About Vacating Your Home During Spray Foam Installation

Evacuating your home can feel frustrating and inconvenient. The reason for vacating is not because spray foam is an unsafe product but because the manufacturing process creates a byproduct that is hazardous to breathe.

After the foam is manufactured and cured, it is safe to return home. This curing process takes approximately twenty-four hours to complete. You can return home as early as a day after the installation.

Now that you know how long you'll have to vacate your home, your next step is to:

• Discover which spray foam is right for you
• Learn what to look for in a spray foam contractor
• Find out what you should know before calling a contractor