Because of its high efficiency, spray foam has become more popular in recent years. KC Spray Foam offers both major types of polyurethane spray foam - open cell and closed cell. While both open cell and closed cell spray foams are great choices, there are some key differences between the two.
Open Cell Spray Foam Kansas City
This low density spray foam is 1/2 pound per cubic foot, water blown and much more sponge-like in appearance than closed cell spray foam. Because the cells are open, it works by trapping the air inside the foam which insulates the air seal. This is a very good barrier against air and sound, but does not provide much protection against water vapor. For this reason, open cell spray foam is recommended for indoor use only.
The average R-value for open cell foams is around 3.5 to 4.5 per square inch. There are no ozone depletion chemicals (CFC, HCFC, fibers, VOC's, formaldehyde, asbestos). It is a two part liquid and expands 120 times itself when sprayed into place. Open cell spray foam is also hydrophobic, meaning it repels and does not wick up water. KC Spray Foam uses Sealection500 open cell spray foam, which stops 94.72% of heat flow with 4 inches of foam.
Closed Cell Spray Foam Kansas City
Closed cell spray foam has a more compact cell structure and is much more dense than open cell spray foam. It is 2 pounds per cubic foot and is very rigid. Instead of using water, closed cell spray foam is blown using a hydroflouro-carbon (which is ozone safe). Closed cell foam is a great barrier for not only air, but also water vapor, meaning it can be used indoors and outdoors with a coating. 
For closed cell foams, the R-value is usually around 6 to 7 per inch and it can also be used as a water vapor retarder after 1.5 inches. Like open cell, it is a two part liquid and expands around 30 to 40 times its size. Although it will not support buildings, closed cell spray foam is very strong; it can hold 25 pounds per square inch. It is not recommended to use closed cell spray foam on the underside of roofs, as a leakage will cause the water to sit on the foam, ruining the roof structure. Our preferred product, Heatlok Soy200 closed spray foam, will stop 94.4% of heat loss with just 2 inches of foam.