Why is SPF the Solution to Roofing Leaks?

Your home is your sanctuary. You carefully create a space where you can relax and enjoy the simple pleasures of life. A leaking roof could disrupt your calm and serenity, though.

There are many reasons why roofs leak. It can be anything from age to damaged roofing membranes, poor installation, and improper use of material. However, you can save yourself from the hassle and headache of roof leaks with spray foam roofing systems.

Why is SPF the solution to roofing leaks? Keep reading to find out.

What Are Spray Foam Roofing Systems?

SPF roofing is a roofing system that uses expanding polyurethane foam to create a monolithic roof surface. The roof’s seamless application eliminates the need for seam joints, tiles, panels, fasteners, and flashings.

SPF roofs are usually formed using a liquid-based isocyanate and polyol fiber dual compound. When you spray the liquid onto a substrate, the two basic compounds combine. It produces a chemical reaction that expands fibers thirty times denser than its liquid form. This revolutionary technology even helped send people to space.

After spraying on the compound and waiting for it to increase in volume and density, the roof is coated with a polyurethane, silicone, or acrylic elastomeric coating. This enhances the roof’s durability, prevents UV ray damage, makes the roof look great, and increases the roof’s lifespan.

How Do Spray Polyurethane Foam Roofing Systems Prevent Leaks?

Since spf is mostly a flat roof/low slope application ponding water is common and inevitable. Ponding water is best prevented by using the slope to drain method where you apply heavier thickness of foam in the low areas and gradually slope the roof ¼” per foot to the drains. The water will drain very slowly and what is left will soon evaporate. The industry standard for ponding water is a 100 sq ft puddle 1” deep for more than 24 hours. Puddles that exceed those dimensions will require more foam to improve the drainage. 

Cell Type

There are two kinds of spray foam cells: open cell and closed cell. They differ on how many cells the foam has after expanding.

Open-cell foams are lightweight foams that absorb water. They are at least 50 percent cells in their structure. Closed-cell foams, on the other hand, are denser foams that don’t receive any moisture. They have, at the very maximum, 10 percent cells in their structure.

SPF roofing foams are dense, closed-cell foams. They don’t hinder water from traveling horizontally throughout the roof. Additionally, the water will sit on the surface until the sun dries it if the roof gets damaged.

Installation Process

Typically, leaks often find their way into the home through the roofing seams. These are the places where fasteners or glues connect the different parts of the roof.

No matter how well you have a conventional roof installed, time will eat away at the bond. As bonds deteriorate, gaps form and become moisture entry points, creating a leak.

SPF roofing systems don’t have this problem, especially since you spray the foam on and merge as it expands. There are no seams where water can enter because the whole roof is one layer.

Roof Penetration Treatment

Roofing penetration refers to anything that can go through the roof. Skylights, HVAC systems, vents, and exhausts are considered roof penetrations.

The difficulty with penetrations is that cutting through the roof leaves gaps where leaks may enter. Contractors will do everything they can to plug up those holes. However, patches could have seams. Despite their best efforts, moisture will find a way through the cracks and into your home.

SPF roofing systems are sprayed on and can get to all the nooks and crannies of the penetrations. This will effectively seal any gaps and save you from facing leaks.


There are many benefits to installing a spray foam roofing system in your home. One is definitely SPF’s solution to roofing leaks.

SPF roofing systems are closed-cell foams that are dispensed through spraying and creating a seamless monolithic roof. This roofing system’s cell type, installation process, and roof penetration treatment all work together to make your roof impermeable to any moisture the elements can throw at it.

Whenever you’re looking for one of the best spray foam roofing companies in Walnut Creek, CA, turn to American Foam Experts. We are a licensed SPF roofing contractor that can meet and exceed all your SPF roofing needs. Contact us for a free quote today!