The importance of good insulation cannot be stressed, but not all insulation is equal. In this video master builder, Matt Risinger discusses why he loves and uses open cell foam insulation in his homes. The reason he's sold on it? It makes for a total fill insulation. Demonstrating its use in a double thick wall, there is 5.5" of foam sprayed giving him an R-value of 3.7/inch. That means, in this demonstration, it equates to an R-20 in the wall. Totally filling means that it doesn't have to be cut. It can go over wires, and it's easy and time-saving to install. Another important factor is that he can achieve air sealing as long as it is a sufficiently thick application. There are two caveats. It can be susceptible to damage on the job since it doesn't have closed cell foam rigidity and you can't get it wet. Its cell structure is similar to a kitchen sponge so it will attract and retain water. Another positive aspect of it is that it sticks to the substrate, which is especially useful when spraying it on ceilings. If you haven't used open cell foam before," check out the blog and see a really good demo of it.