Jan 10, 2020

Open Cell vs. Closed Cell Spray Foam Insulation For Your Attic

While spray foam insulation may appear to look the same, it’s offered in both open cell and closed cell.  Which material your insulation contractor opts for can have a significant impact on your attic’s R-value and the overall energy efficiency of your home.  Here’s what you need to know.

Consider Density When Selecting A Type Of Spray Foam Insulation

One of the biggest differences between open cell foam insulation and closed cell foam insulation is their densities.  Closed cell insulation is heavy and inflexible, where open cell spray foam insulation is more flexible and forgiving.  The type of application should be taken into consideration when deciding which type of spray foam insulation to use.  For example, in a home with new electrical, open cell tends to work better because it is easier to manipulate.  However, in a shed, the closed cell’s rigorous properties work well because it can better withstand impact.

spray foam

Expansion Rate of Open Cell & Closed Cell Foam Insulation

Another way in which the two materials vary is how much they expand when they are applied. Open cell insulation has a much greater expansion rate, also known as high expansion foam, which is helpful when trying to fill all surface crevices in attics, rim joists, and crawl spaces. Closed cell or low expansion foam has a much lower rate which works well in other scenarios.

High Expansion Foam Helps With Sound Reduction

If one of the major goals of the spray foam insulation project is to reduce noise, open cell spray foam insulation will do a better job.  This is because it expands at a higher rate and can fill in all fissures that may be allowing noise to enter a space.

Low Expansion Foam Has Less Moisture Absorption

Closed cell spray foam insulation’s rigid consistency allows it to have a lower moisture permeability rating compared to open cell spray foam insulation.  Closed cell foam insulation works well in attics, most notably when applied to the underside of the roof deck, as it will prevent moisture from being transmitted.

Insulation R-Value

R-value measures the ability of a material to insulate and combat the flow of heat.  The higher the R-value, the more effective the material is.  Because of its density, closed cell foam insulation has a higher R-value than open cell foam insulation.

Price of Spray Foam Insulation Options:

Both types of insulation utilize a blowing agent to fashion the cells inside it.  Water is the blowing agent for open cell insulation, whereas closed cell spray foam insulation uses chemicals in addition to water, adding to its expense.  The density of closed cell spray foam insulation also means that more of the material must be used than if the same space was being insulated with open cell spray foam insulation.

Watch Our Insulation and Ventilation Experts in Action:

Considering a do-it-yourself approach? Check out the Top 5 Rookie Mistakes Made During DIY Spray Foam Insulation.


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Insulation and Ventilation Reviews:

"We hired Lindus for attic insulation and new LeafGuard® Gutters. We had an issue arise a couple years after the work was completed. I called Lindus and had no problem scheduling someone to review and create a plan. Randal has worked diligently to get to the bottom of the problem and fix it permanently. The company truly does stand by their product, a claim that is not always realized, but with Lindus has proven to be true. I am so appreciative and would recommend them to anyone."

Sarah W.
Edina, MN
May 30, 2022

"On two occasions, Randall was at my house involving insulation issues.  He knows the business, is easy to work with, and I think he is a great asset to your company."

Mary W.
Maple Grove, MN
May 2, 2022

"They were contracted to insulate the garage ceiling which they did in a two-step process with both foam and blown-in insulation. They then returned to put up new gutters facia and soffits in a two day process that was professional, neat , and used materials economically."

Stephen G.
MInneapolis, MN
April 28, 2022

"Excellent and efficient work. Thankful that the Lindus crew was accommodating to our needs as homeowners and for their communication throughout."

Bloomington, MN
April 19, 2022

"Had Lindus blow in foam insulation into attic, what a difference it’s made! The house is noticeably warmer in the winter and my furnace is not running nearly as much as before. I know it will also help keep the house cool in the summer heat. They also installed some new windows and exterior trim. Everything turned out really well. Corey Hessler was fantastic in dealing with from start to finish and answered all my questions. Everyone I dealt with from Lindus, especially Corey, were kind and professional. In today’s day and age you get what you pay for. Lindus really delivers!"

Robert M.
Cottage Grove, MN
March 25, 2022

"We highly recommend Lindus Construction. They showed up everyday and did quality work. Very professional, polite, and answered all of our questions and concerns. The work ethic we saw was superior. We’re very pleased with the insulation and venting project they just completed. They get the highest a 5+ rating from us."

Lee Ann S.
Maplewood, MN
February 4, 2022
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