What's the difference | expanding foam and spray foam?

2/3/20241 min read

What is the difference between expanding foam and spray foam?

Expanding foam is used for upright applications. The foam can be poured into cracks and crevices to fill voids. Spray foam is another form of expanding foam. It can be sprayed onto a surface at angles that would be hard to pour on. It sticks to the surface and can be installed on walls and ceilings.

What is spray foam?

Spray foam is a mixture of two chemicals that come together to create foam. Spray foam is used as an insulation, packing material, or moisture barrier.

The foam is built from thousands of tiny air pockets that form the rigid structure. The air pockets keep our houses warm by making it hard for heat to escape. Each bubble is totally enclosed. This keeps moisture from passing through the structure. These bubbles are known as cells.

Types of spray foam

Spray foam insulation falls into two categories. Closed cell insulation is made of millions of tiny bubbles that form the structure. The closed cells are unique because they expand slower than other spray foams. The slower expansion makes the foam more waterproof. Open cell insulation is a rapidly expanding spray foam that expands to a much higher volume. This makes open cell foam a great sound barrier but susceptible to water damage over time.

Want to learn more?