Open Cell Vs Closed Cell Spray Foam Insulation

Not sure which spray foam is the right fit? This should help!

It’s clear that spray foam can be a great insulation method for your home. Spray foam is a great way to regulate the temperature of your home. It can keep the indoors comfortable in the summer and warm in the winter. There is one problem that spray foam buyers face when trying to decide whether they should buy closed-cell or open-cell.

These are the two types of spray foam insulation and they serve two very different purposes. 

These differences are due to the job the foam can do once it is sprayed onto a surface.

What is Closed Cell Spray Foam?

Closed-cell spray foam of polyurethane is the most popular. Because of its high R value, it’s considered to be a closed cell. R-value refers to the material’s ability to resist heat flow and insulate. Insulation is more effective if the R-value is higher. Closed-cell spray foams are resistant to water, and can prevent moisture buildup by resisting water seepage. Moisture buildup can promote mold and bacterial growth.

Closed-cell spray foam has a higher density and is used to insulate appliances and buildings. It can be used to insulate both the inside and outside of an insulated object.

What is Open Cell?

Open-cell spray foam behaves in a similar way to closed-cell spray foam. It has a lower R-value. Open-cell foams have a lower R-value at between 3.6 and 3.8 inches. Closed-cell spray foams are typically above 6.0 inches. Open-cell foam expands as soon as it is applied. This makes it ideal for difficult to reach places. Open-cell foam can be used to fill in those nooks and crevices.

Open-cell spray foam may not be as water-resistant as closed-cell. This foam is lighter and provides less support for walls. It is also permeable to air and vapor, which will lower the noise frequency ranges.

Closed-cell spray foam will provide strong insulation. For smaller fill-ins, an open-cell foam is fine.