Open & Closed cell
After looking around for a while and comparing the different types of insulation methods out there, maybe by now you have rightly decided spray foam insulation is by far the best. The benefits it offers are great and the savings you get are very worth the effort and upfront cost. Some of the benefits are the great insulating factor and air sealing, especially in those hard to reach areas that can cause air leaks, you save up to 30% or more on utility bills and best of all you get a superiorly comfortable home.
Two Types of Spray Foam
There are two main types of spray foams, they are known as Open Cell and the other one as Closed Cell. What is the difference you may wonder? These two types of spray foam are made from pretty much the same base products, but mainly differ in their density. If you have a higher density, it becomes heavier, stronger and offers a better insulating factor. Both of these, open and close cell insulation, are proven to be effective but they each have their own unique qualities. Lets take a look at each one of these.
Open Cell Spray Foam
First, we will look at Open Cell Spray Foam. Open cell foam is pretty soft, a little bit like a cushion. The cell walls of this material are slightly broken and air will be able fill all the spaces. When open cell foam is applied, it will expand rapidly to about 100 times its original applied thickness. This allows it to reach all those nooks and crannies and areas that are hard to reach, this can include ceilings, walls, joist ends and other air infiltration prone areas. Thanks to its fast expansion and coverage, it will seal the area and therefore allow proper insulation. Open spray foam does not provide water resistance and its low strength provides much less support to the walls. Open cell foam is usually limited to interior use. Its Standard R-value is about 3.8 per a inch of thickness, but its Effective R-Value is about 7.2 per inch of thickness. The biggest
benefit of open cell vs closed cell is the fact that it is allot easier to work with and it is allot cheaper to apply. Usually Open cell can be up to 60% cheaper than closed cell. Due to the fact that open cell spray foam is not a vapor barrier it is best used in low humidity parts of the
country or with home that has a separate vapor barrier installed.
Closed Cell Spray Foam
Closed Cell Spray Foam is strong enough to walk on without to much distortion. In closed cell foam, the cells (or bubbles) are not broken this makes it much stronger and rigid because the bubbles in this material are so strong that they can take a lot of pressure. These cells (or bubbles) are full of a special type non-toxic gas that makes this insulation have the highest insulation value possible. Its Standard R-value is usually around 7 per a inch of thickness and its Effective R-Value is about 14 per inch of thickness. Closed cell foam has a much higher density than open cell foam which provides superior insulation & sealing of both vapor and air. This added vapor barrier function is highly valuable especially in high humidity areas due to the fact that it can function as a highly effective primary vapor barrier, this in-turn can help eliminate mold growth in your home. Also unlike open cell, closed cell foam can be used externally to insulate outside structures. Another interesting fact about closed cell spray foam is some studies have shown that when applied on structures it can add up to 30% strength due to its rigidity and stickiness. It truly is an amazing product.
As you can see they are similar but differ a little as well. Closed cell foam has a lot more advantages for example its strength, its higher R-value, and its high resistance to vapor infiltration. Some of its disadvantages is its higher cost since it is more dense and requires more material usage. Both of these are commonly used and the choice on which you decide to use will depend on the conditions of each homes geographic location, surrounding environment and individual needs. When considering what insulation type to use it is best to consult a professional to review your project’s needs.