Closed- And Open-Cell Spray Foam Insulation: A Breakdown With Pros And Cons

Posted on: 6 July 2020


As a homeowner, choosing to add insulation to your home can be a serious decision. While many homeowners know a bit about home insulation, some are also surprised to learn there are so many different types. Spray-foam insulation is perhaps one of the most common choices because it is easier to add to an existing structure, but there are also two primary types of spray foam insulation: closed and open-cell. To get more familiar with your options before you call the insulation company for help, here is a brief breakdown of each type of insulation with pros and cons to consider. 

Closed-Cell Spray Foam Insulation 

Closed-cell spray foam insulation is not constituted with bubbles or air pockets (open cells). The foam is formulated with different ratios of oxygen and ingredients, so when the foam is sprayed in place, it creates a harder insulation product that is not soft or springy. The foam is more dense and solid so air does not travel through the material once it cures. Closed-cell spray foam insulation is commonly installed in homes and other structures, but it tends to work out best in certain areas. 


  • Works well for outdoor applications 
  • Can be used to help generate more stability for a structure
  • Does a good job of thwarting moisture or vapor issues 
  • Can have a higher R-value rating than open-cell spray foam insulation


  • Does not expand as much as open-cell spray foam 
  • Does not work all that well for soundproofing a space
  • Does not work the best in already-built structures

Open-Cell Spray Foam Insulation 

Open-cell spray foam insulation is probably the more common form of spray foam insulation used in residential settings. This insulation has open cells, which means it has more void space and bubbles inside the foam. A different formulation generates these air bubbles during application, and the end result is a softer foam product that does work well for insulating everything from walls to ceilings. 


  • Expands a great deal during installation 
  • Works well for soundproofing interior walls and ceilings 
  • Has a good R-value compared to rolled batt insulation 
  • Excellent option for existing structures and good for filling small spaces


  • Does not have the same R-value of closed-cell spray foam 
  • Does not thwart moisture and vapor issues as effectively 

Regardless of what type of insulation you choose for your home, it is good if you know a bit about it. Reach out to an insulation company to learn more about different types of insulation, their benefits, and how well they will work for your planned project.