Spray polyurethane foam (or “SPF” or “spray foam”) is a rigid foam plastic that can be used for insulation in walls and attics, under roof decks, and on roofs and exterior walls. It air seals around walls, roofs, and corners as well as on contoured surfaces.
SPF has been improving building performance since the middle of the 20th century.
Spray polyurethane foam consists of two primary components: an isocyanate (A-side) and a polyol (B-side). In addition to spray polyurethane foam insulation, isocyanates and polyols are used in the production of things like refrigerator insulation, couches, mattresses, footwear, sports equipment, paints, and glues.
Some varieties of SPF use catalysts to speed up the reaction, and other substances can be added to give the product a variety of properties, such as durability, breathability, firmness, or fire resistance. These additives vary based on the desired outcome and specific product.
Spray polyurethane foam is made by mixing the two liquids isocyanates and polyols.
Isocyanates and polyols react quickly, creating foam which expands within seconds to fill in the spaces being sprayed before it sets. Once formed, the foam sets very quickly. Spray foam insulation is effective in sealing air leaks as well as insulating due to its dense final consistency.
As with any energy efficiency home improvement project, you should consider not only the upfront cost of spray polyurethane foam (SPF), but the future savings on energy bills. SPF can help lower energy bills by reducing air leaks, which improves a home’s energy efficiency by decreasing the transfer of heat between the indoor and outdoor environments. The average payback period for SPF can vary greatly depending on the home, your energy usage, the environment, and other factors.
Spray polyurethane foam (SPF) adheres to the wall, forming a continuous insulation and air barrier on the surfaces and cavities to which it is applied, even on contoured surfaces. SPF’s properties as an air barrier make it unique because a separate barrier does not have to be installed as an additional step in the retrofit or construction process.
Spray polyurethane foam (SPF) insulates and acts as an air barrier, both of which are critical to making your home comfortable and reducing heating and cooling costs. There are no pieces to cut or seams to tape or caulk. In addition, SPF may reduce sounds transmitted through the air, add structural strength, and improve moisture control to help resist the formation of mold.
Spray polyurethane foam (SPF) resists heat transfer extremely well, helping you keep hot air out during the summer and warm air in during the winter. Open-cell foam, closed-cell foam, and roofing foam all provide high R-values and act as effective insulation. R-values measure the thermal resistance of insulation, and a higher R-value means that the material is more resistant to heat passing through it, which makes the material a better insulator.
Open-cell SPF typically has an R-value between R-3 and R-4 per inch, and closed-cell SPF typically has an R-value between R-6 and R-7 per inch. R-values are often listed at 1-inch depth for ease of comparing insulation products. To find out the R-value for a specific insulation, refer to the product’s label or technical data sheets, often available online. R-value also determines how thickly a product must be applied to meet insulation needs.
SPF is also highly effective at keeping outside air from coming into a house through cracks, seams, and joints because it forms an air barrier, which means less energy is needed to heat and cool a home. Air infiltration accounts for as much as 40 percent of the energy a home uses for heating and air conditioning, according to the ENERGY STAR program. Spray polyurethane foam offers a highly efficient one-step solution to this problem.
Information courtesy of | Spray Foam Coalition Visit www.whysprayfoam.org for more information.
Spray polyurethane foam (SPF) can serve as insulation on the interior of a home or building, in walls, ceiling, and attics. It can be applied around corners and on all contoured surfaces. In some regions of the United States, homes with low-slope or flat roofs can use high-density SPF as a roofing material, or as a replacement for insulating sheathing, to provide high protection against heat and water infiltration. SPF can also strengthen the entire structure to which it is applied and increase a building’s resistance to wind uplift.
Spray polyurethane foam (SPF) resists settling, structural deterioration, and decomposition over time. In most wall and roof cavity applications, SPF should last the lifetime of the building. Ask your contractor for more information about the expected lifespan of the SPF being installed in your home.
Just like other home projects, installing spray polyurethane foam can cause odors for a limited period of time. When having spray polyurethane foam installed, talk to your professional contractor about the product’s curing time and safety practices. During installation, homeowners, their children, and pets leave the home or building. Your professional contractor wears personal protective equipment during and immediately following the application of the product. According to the U.S. Environmental Protection Agency (EPA), after spray polyurethane foam cures, it is considered to be relatively inert, which means the chemicals are finished reacting.
Installation time varies significantly depending on the size of the job and the ease of access to the site. When having spray polyurethane foam installed, talk to your professional contractor about the amount of time it takes to install the product and its curing time and safety practices. A small amount of spray polyurethane foam (SPF) applied to a home’s interior can take as little as one to two hours to complete. Insulating an attic or basement in most normal homes can be completed in less than a day. It is important to remember that while the foam can be installed fairly quickly, homeowners, children, and pets leave the home for the amount of time recommended by the SPF manufacturer.
With proper mechanical ventilation, homeowners are unlikely to smell odors from spray polyurethane foam insulation after it has been applied and allowed time to cure. If you are concerned about odors after the spray polyurethane foam installation, contact your professional contractor.
Homeowners, their children, and pets leave the home during the installation process. There are a number of variables that determine the length of time you must stay out of the house, including temperature, humidity levels, and the SPF’s formula. Homeowners should discuss the amount of time they need to wait before reentering their home with their contractor.
Spray polyurethane foam (SPF) products, as well as most other materials in homes, are designed to meet all applicable building and fire code regulations. SPF is an organic material and like other organic materials such as wood, paper, cotton, wool, and many others, it can ignite and burn if exposed to a sufficient heat source. To learn more about the properties of a particular SPF product, ask your contractor or the product manufacturer.
Manufacturers can usually provide reports from independent laboratories and/or building code evaluation services that verify building code compliance.
Spray polyurethane foam can help minimize airborne sound transmission. Open-cell foam can reduce high-frequency noise, and closed-cell foam can reduce low-frequency noise. A combination of open- and closed-cell foams can help maximize noise reduction. It is important to keep in mind that proper sound control involves specific design elements and construction techniques, including layering of materials to achieve desired performance, not just the use of specific products.
When having spray polyurethane foam (SPF) installed in your home, work with a professional contractor who can educate you on the installation process. A professional contractor can explain the benefits of SPF as well as safe use and handling practices during installation.
There are several ways to find a professional contractor, including the membership directory of the Spray Polyurethane Foam Alliance, which lists contractors by location. It is a good idea to ask contractors about their experience and training and to provide customer references. Because the applicantion of spray foam requires accuracy and precision, homeowners should hire a certified SPF contractor. Information courtesy of | Spray Foam Coalition Visit www.whysprayfoam.org for more information.
There are several different types of spray polyurethane foam (SPF), each having their own advantages. It is generally categorized by the type of cell, or particles, of the foam; the density of the foam; and the way it is applied.
- Open-cell or closed-cell: First, spray polyurethane foam can be open- or closed-cell. This refers to the tiny particles or cells of the foam itself and the form they take.
- High-, medium- or low-density: Second, spray polyurethane foam is described by its density. For example, closed-cell foams can be high-density or medium-density for use on roofs, building exteriors and large wall applications. Open-cell foam is low-density and is often used for interior cavity fill and unvented attic applications.
- High-pressure, low-pressure or foam sealant: Finally, spray polyurethane foam is described by the way that it is applied, using high pressure systems, low-pressure systems, or cans of already-mixed foam sealant. The low-pressure sealant is also sometimes called foam-in-a-can.
A professional spray polyurethane foam contractor can help you choose the best type of foam to fit your project. It is important to discuss with your contractor what type of SPF insulation is best suited to your application. This chart provides more information about the typical characteristics and differences between open-cell and closed-cell foams:
|Higher R-value (greater than 6.0 per inch)||R-value (approximately 3.5 per inch)|
|Lower moisture vapor permeability (low perm)||Higher moisture vapor permeability, but controlled|
|Air barrier||Air barrier at full wall thickness|
|Higher strength and rigidity||Lower strength and rigidity|
|Resists water||Not suggested for applications in direct contact with water|
|Medium density (1.75 – 2.25 lbs/ft3)||Lower density (0.4 – 1.2 lbs./ft3)|
|Absorbs sound||Absorbs sound very well|
High-pressure two-component SPF systems are used when insulating larger areas, such as walls and roofs on new construction or major renovations.
These products are not a Do-It-Yourself (DIY) project and are designed for professional use. These systems require special training and the use of specialized personal protective equipment (PPE), including respirators. When high-pressure two-component spray polyurethane foam insulation is needed, an SPF contractor having the proper training, equipment, and personal protective gear to handle these large-scale projects should be hired.
When applying two-component low-pressure SPF, building and home owners need to consider a trained professional contractor. Trained professional contractors have access to a wide variety of training; are familiar with important safety precautions, local codes, and regulations; and can offer guidance about the type and amount of insulation.
There are insulating foam sealant products available in cans for do-it-yourselfers at home improvement stores. These products are used for small “bead-type” applications, such as sealing windows and doors, or filling small gaps and cracks.
Retrofitting one’s home with spray polyurethane foam (SPF) may help homeowners qualify for tax credits, rebates, and other incentives that can help offset renovation expenses. To find available local and state incentives, visit the Database of State Incentives for Renewables & Efficiency (DSIRE) at www.dsireusa.org. For more information on Federal incentives, visit www.dsireusa.org or the ENERGY STAR® webpage.
Like spray polyurethane foam (SPF) insulation, SPF roofing is very similar to closed-cell SPF insulation, but it has a higher average density and is thus more rigid. It is created in the same manner as high-pressure SPF insulation by mixing liquid chemicals on the job site to create high-density foam that is impervious to water, allowing it to serve as a very effective roofing material. In some regions of the United States, homes with low-slope or flat roofs can use SPF to improve the home’s air seal and lower heating and cooling energy usage. SPF roofing provides high protection against heat infiltration, strengthens the entire structure to which it is applied, and can increase a building’s resistance to wind uplift.