Can Spray Foam Insulation Be Left Exposed? (Find Out Now!)

Upgraded Home Team
by Upgraded Home Team

Spray foam insulation is a great product that is widely used in buildings and homes alike. This product is easy to install, lasts a long time, and can repel mold, mildew, and unwanted pests away from your home. Although spray foam insulation may be more expensive than traditional rolled insulation, it is a cost-saving product that will save you money in the long run through its energy efficiency and long lifespan.

Building codes in some municipalities require that you cover your spray foam insulation. Other areas require that you only cover spray foam insulation if the living space is directly exposed to it. Spray foam insulation is flammable and dangerous if left unexposed, and covering it with drywall reduces the risk of fire.

Spray foam insulation can be used on the exterior portions of your home as well. If you are using spray foam insulation on an outer wall or plan to leave it exposed, the insulation can be left uncovered. Consider, though, that leaving your spray foam insulation uncovered can cause it to degrade faster than usual.

Spray foam insulation can degrade with prolonged exposure to UV light which comes from sunlight. Consider applying plywood or simple paint over spray foam insulation to protect the product’s integrity for a more extended period.

Do You Need Insulation Installers?

Get free, zero-commitment quotes from pro contractors near you.

Is Spray Foam Insulation Fireproof?

Although many materials in your home are designed to be fireproof, spray foam insulation is not one of them. This combustible material commonly found in homes and buildings can easily ignite if exposed to a strong enough heat source. This characteristic is why foam insulation is often considered a combustible material. If you are using spray foam insulation in your home, it cannot be left exposed within the walls.

Many local building codes consider this a fire hazard and require some thermal break, usually in the form of drywall, to prevent the spread of a fire.

At What Temperature Does Spray Foam Insulation Combust?

Spray foam insulation is a durable material but must be covered to prevent the spread of a possible fire. The materials used in spray foam insulation are combustible and can easily cause a fire to spread throughout your home. Most spray foam insulation products will combust when they are exposed to temperatures starting at 240 degrees F.

Although this seems like an extraordinarily high temperature, under the right conditions it is completely possible to achieve this temperature within the walls of your home. It is possible for your insulation to catch on fire and spread through your house at this temperature.

How is Spray Foam Insulation Traditionally Covered?

Whether you are covering your spray foam because it is required to meet building code or simply want to preserve your insulation for a longer period, there are two main ways to cover the insulation. First, it is quite common to use drywall to create a thermal barrier. Drywall is sometimes referred to as gypsum board or sheetrock. Be sure to purchase at least 1/2 inch thick drywall to create a thermal barrier and meet the building code.

Alternatively, if you are not required to meet a specific building code, simply covering spray foam with plywood is a suitable option. The plywood will protect your spray foam insulation from UV light and will keep the insulation weather protected. It is important to remember, though, that plywood is not fireproof and will often not be enough to pass the local building code.

How Is Spray Foam Insulation Made?

Spray foam insulation is a synthetic material that is made of isocyanate and polyol resin. These materials are pressed together and processed to create foam. Polyol is a polymer made from organic materials and is the most prevalent material found in spray foam insulation. While this technology has been in existence since at least 1940, it really didn’t come into popularity until the 1970s. Today it is a widely used and sought-after product because it has several benefits compared to traditional insulation.

When choosing spray foam insulation, there are two forms. Homeowners will be able to choose from open-cell spray foam insulation and closed-cell spray foam. Typically, open-cell is a better sound insulator and is widely used throughout homes and between rooms. Comparatively, closed-cell spray foam insulation is thicker, with a higher density. This spray foam insulation option means that the closed-cell spray foam has a higher R-value and will retain temperature better.

What Are the Benefits of Spray Foam Insulation?

Spray foam insulation is widely becoming the popular choice for home design and has several additional benefits compared to traditional rolled insulation. First, spray foam insulation works better to insulate your home, providing more controlled temperatures.

If applied correctly, spray foam insulation can also help reduce noise throughout the house and create a quiet noise barrier from room to room. Further, spray foam insulation is long-lasting and will not compact and degrade over time like traditional insulation.

More so, spray foam insulation has several properties that can help prevent unwanted guests in your house. Pests and insects do not like what spray foam is made of, so it works as a repellent against pests. Plus, spray foam insulation can also repel mold and mildew from your home, preventing ongoing allergies or respiratory problems into the future. Although spray foam insulation is marginally more expensive to install, this product’s benefits far outweigh the additional price.

Can Spray Foam Insulation Be Used Outside and Left Uncovered?

Usually, spray foam insulation is used for indoor applications, but it can certainly be used on exterior walls or outdoor applications. It is best to keep spray foam insulation covered and not exposed to the elements. Not only is spray foam not fire-rated, but it will quickly degrade and break down when exposed to UV light from the sun.

Spray foam insulation that is left uncovered outside will be subject to a great deal of sunlight and will only last a fraction of the time outdoors and exposed.

If you plan to use spray foam insulation outdoors, it is good to cover the spray foam with protective paint. Not only will the paint help to insulate the spray foam from light damage, but it will provide some weather barriers too. Painting the spray foam will help the spray foam last longer. If your paint is exposed to the elements outdoors, be sure to find an all-weather paint that will hold up to varied climate changes.

Do You Need Insulation Installers?

Get free, zero-commitment quotes from pro contractors near you.

Related Questions

Is Spray Foam Insulation Safe to Breathe?

Applying spray foam to the interior walls of your house is a process that emits aerosols and vapors. Although the materials used in spray foam insulation are generally safe, the exposure when spraying this material exceeds the recommended safety limit established by OSHA. If you are spraying foam installation in your home, it is always best to have a high-grade respirator to help keep you safe. A respirator will also help to protect your eyes and skin from possible irritation.Luckily, once spray foam insulation is installed and left to settle, it is a safe and very durable product. Unlike other insulation materials that can settle over time, spray foam insulation will stay in the place where it is sprayed.After the initial installation, it is possible to work and move around dried sprayed foam insulation without the use of a respirator to breathe. This material is mainly made of organic materials that are safe to have in your home.

How Long Does it Take Spray Foam Insulation to Off Gas?

When you initially install spray foam insulation in your home, it will create powerful gases that can be caustic and dangerous if you breathe them in. After applying spray foam insulation to your home, you must give the material time to dry and settle, allowing some potent gases to off-gas from the installation.Usually, the spray foam insulation will be safe to be around after about 8 to 24 hours. After this period, the gas has enough time to dissipate, making it safe to be around your spray foam insulation without wearing proper protective equipment like a mask or a respirator. Of course, always check with your particular spray foam insulation product to confirm the drying time after installing the insulation in your home.

Upgraded Home Team
Upgraded Home Team

We are a team of passionate homeowners, home improvement pros, and DIY enthusiasts who enjoy sharing home improvement, housekeeping, decorating, and more with other homeowners! Whether you're looking for a step-by-step guide on fixing an appliance or the cost of installing a fence, we've here to help.

More by Upgraded Home Team