CLOSED CELL FOAM
This offers all the benefits that open cell does and the added plus of having higher density, this means waterproof protection. CC is also a great reinforcer of structures, main reason why its more common us is for outside jobs.
Closed cell is the denser and more common of the two types of polyurethane spray foam. The common measurement system for foam resistance to heat flow (i.e., insulation) is a foam’s “R-Value.” Closed cell polyurethane foams have higher R-values than other types of foam, around 6.8 per inch, although some stronger ones have R-values of 7.14 per inch and higher. Closed cell foams feature better insulation because of this resistance, and are also more resistant to water degradation or penetration, which includes moisture build-up. Moisture can eventually attract bacterial growth, promoting mold, which can eat away at wood and compromise structural integrity. Preventing moisture migration can help greatly curb mold growth.
It´s also dense enough to insulate air, preventing drafts and keeping in regulated temperatures. This density also prevents mold growth because temperature control can cut down on humidity, which spawns mold. In order to maintain their resistance, closed cell foams are usually dense and strong, and resemble solids when they fully form. This strength not only helps to insulate buildings and appliances, but can also strengthen walls to which it is applied.