The Benefits and Drawbacks of Spray Foam Roofing Systems

In this article, you’ll discover the benefits of spray foam roofing, including:

  • Installation and life-cycle costs
  • They are simple to set up (reduces labor costs)
  • It has the greatest R-value per thickness inch.
  • It is simple to keep. 
  • It is flawless
  • It has closed-cell qualities (which means it will not leak) and is ecologically beneficial.
  • It is both renewable and sustainable.

However, nothing is perfect. We’ll also discuss the disadvantages, such as:

  • There are some untrustworthy spray foam contractors out there.
  • Overspray is a persistent problem.
  • And it must be at least 50 degrees to be installed.

As a result, you are aware. Since 1979, roofing contractors have specialized in industrial spray foam roofing projects. We’ve seen the good, the terrible, and the ugly when it comes to spray foam.

A spray foam roofing expert with over 30 years of experience evaluated, revised, and approved this article for publication.


Costs of Spray Foam Roofing

Spray foam roofing will cost between $8 and $12 per square foot in August 2022. Many factors influence the price. The installation fee is comparable to that of other traditional roofing systems.

Did you know that spray foam may be applied to most existing roof systems? This can help to reduce tear-off costs. It’s also better for the environment because you’re not adding to landfills.

Spray foam roofing is a better long-term cost play because they can be recoated once their guarantee expires.

A foam roof can be recoated (or replaced) for 33% to 50% of its original cost. Removing and replacing a typical roof after the warranty expires is 100% of the installation cost.


Simple Installation

The simplicity of installation might save you both time and money. The foam and coating are applied quickly. It can be implemented without disrupting the facility’s daily operations.

Spray foam roofs are placed by spraying a liquid over an existing roof and allowing it to froth up.

Because of this procedure, the foam can conform to all roof forms and types, even oddly shaped roofs.

After the previous roof has been cleaned, the spray foam roof can be put directly over asphalt, shingles, concrete, metal, and wood.


Efficient Energy Use

Spray foam roofing provides thermal, air, and moisture barriers to produce the best R-value per inch, implying that the material provides better building insulation.

Polyurethane foam keeps heat in during the summer and out during the winter, cutting energy expenses for facility owners. The silicone top coating protects the foam and reduces heat absorption by resisting UV rays (emissivity).


Simple to Maintain

Once completed, a spray foam roof requires little preventative care and repair. Your spray foam roof can survive over 50 years if properly maintained.

Spray foam roofing systems should be inspected twice a year, in the spring and autumn. Further examinations are suggested to follow any occurrence that may have caused system damage.

If silicone recoating is required, there is no need to remove the existing materials; apply the new coat on top of the existing system.



Seams and penetrations most commonly cause roof leaks. This susceptibility is eliminated via spray foam. Because spray foam is sprayed as a liquid, it may cover gaps, cracks, and fractures in the existing roof and substrate.

The application of polyurethane foam allows the contractor to level out the roof and reduce the possibility of ponding water.

The foam material can expand and compress in response to ambient conditions, limiting the possibility of cracks and splitting.

Traditional roofing systems must cut the membrane and employ adhesives, termination metal, screws, fasteners, and other materials to make penetrations watertight. A penetration is anything that comes through the roof, such as an HVAC unit, skylight, pipe, or anything else.

None of these components are required when spray foam is applied fluidly. The penetration is waterproof after the foam is sprayed around it.



During its lifetime, spray foam roofs generate minimal to no trash. In most situations, just the wet and saturated sections of the original roof are removed, resulting in minimum stripping of the existing roof.

On top, a spray foam roof is built, removing the requirement for costly roof tear-offs and waste.

Environmentally friendly products are also used in spray foam roofing systems:

  • No risk of ozone depletion exists (ODP)
  • Volatile organic compound emissions are minimal (VOCs)
  • There are no chlorofluorocarbons present (CFCs)
  • Very Low Potential for Global Warming (GWP)


Closed Cells Properties

If a spray foam roof has a cut, puncture, or hole, it will not leak. This is due to the closed-cell nature of the foam. Water will remain in a hole rather than moving south into the roofing system:

The opposite is true for polyiso boards and other typical forms of insulating wood. Because these types of insulation are open-cell, water can move vertically and horizontally, saturating additional roofing material.

Even if there is a little elevation (or puncture) in the membrane of single-ply insulation, water will enter and saturate more of the insulation. This can result in a time-consuming repair and water entering your building.


Renewable and Long-Term

The spray foam roofing system is made up of four parts:

  • The four components of a spray foam roofing system. 
  • The spray foam roof’s two layers will naturally fade away over time.

For example, a 30-mil coating thickness will be put on a spray foam roof with a 20-year warranty. There will likely be 7-8 mils of coating left in year 20.

A contractor can clean the roof, add a new 30-mil coating thickness, and provide you with a 20-year warranty.

This is how a spray foam roof may be refreshed regularly. Spray foam is long-lasting because it does not lose R-value or performance metrics over time.


Pros and Cons of Spray Foam Roofing

There are some terrible spray foam roofing companies around.

Spray foam application is a procedure that must be carried out correctly from the outset. The contractor must be precise in his application and understand the materials involved.

Spray foam roofing does not need a huge installation crew. It does, however, need a high degree of technical expertise and experience.

The Spray Polyurethane Foam Alliance (SPFA) offers an ISO-17024-compliant certification system with several levels that require contractors to pass an exam and achieve certification requirements.

Poorly built roofing systems may shorten the lifespan of the roof and the underlying substrate.

Choose a contractor with a track record of installing long-lasting spray foam roofing. They should be able to provide a list of foam roofs that they have maintained and recoated.

Limited Installation Period

Spray foam can only be used when the temperature is at least 50 degrees Fahrenheit. When there is ice, frost, surface wetness, or apparent dampness on the current roof, a spray foam roofing system cannot be installed.

While the installation does not disrupt the building’s normal operations, the weather requirements may leave only a brief window of opportunity.

Overspray Potential

The wind and land may transport overspray from the spray-applied spray foam roof on surrounding automobiles and other objects.

While this does not represent a health risk, it does pose a risk to the adjacent property.

They take special precautions to avoid overspray. They use a variety of strategies to safeguard the adjacent property.



Spray foam roofing systems have several advantages, including environmental friendliness, renewable and long-term use, minimal installation crew requirements, and a limited installation period. On the other hand, spray foam roofing should be done only by experienced professionals to avoid overspray potential. Spray foam roofs can provide buildings with an effective roofing system that will last for many years.