When it comes to insulation, there are two main types of spray foam insulation to choose from: closed-cell and open-cell. Each type has its own unique benefits and drawbacks, so it's important to understand the differences between them before making a decision. Closed-cell spray foam is denser and more effective against moisture and vapor, providing up to an R-6.5 of insulation per inch. Open-cell spray foam is lighter and less dense, making it better suited for indoor applications with a higher risk of moisture.
It also has a higher thermal conductivity, meaning it's less effective at preventing heat transfer.Spray foam works by spraying small areas of the interior walls of the house to fill even the smallest cracks and provide optimal insulation capacity. Not all open-cell spray foams are hydrophobic, so be sure to check that the product you're buying is actually hydrophobic, like Icynene's classic ultra open cell spray foam. This method of application allows for an even distribution of spray foam insulation inside walls and ceilings.If you look at the culmination of the expansion, density and cellular structure of each type of spray foam, the R-value corresponding to each one will make a little more sense. Both types of spray foam work to create an airtight seal and prevent moisture infiltration, making them valuable insulation options.
With the right thickness and applications, closed-cell spray foam does not allow steam or water to pass through due to its closed and compact cells.Open-cell spray foam is less expensive than closed-cell because it costs less to manufacture the material itself, as well as to the expansion and cell composition of the sprayed open-cell foam. If you need to spray the outside of your building or if you have the opportunity to be exposed to water on an ongoing basis, then you should opt for closed-cell foam, as it doesn't let water through, can reject bulk water, and is approved by FEMA.Homes where Icynene spray foam has been installed usually have an ACH (hourly air changes) of less than 3, which is considerably lower than what is required by the most common building codes. Closed-cell foam sprayed in situ typically has an R-value of 7 per inch, while open-cell foam typically has an R-value of between 3.5 and 4 per inch sprayed. As closed-cell foam is denser than open-cell foam, more material will be needed to cover the same amount of space, so it will ultimately cost more.So which type of spray foam insulation should you choose? Ultimately, it depends on your needs and budget.
If you're in an area with a building code that requires a higher R-value in certain areas, you may need to opt for closed-cell foam to meet those code requirements. On the other hand, if you're looking for a cost-effective solution that still provides excellent insulation capacity, then open-cell spray foam may be your best bet.
