What are the differences between open cell and closed cell foams?
Open cell is much lighter and softer being only a 1/2 pound per cubic foot. The two pound in much harder and tougher. The open cell gives you two barriers a thermal and a air barrier. The closed cell gives you four barriers, a thermal, air, moisture and vapor barrier. (Note fiberglass only gives you a thermal barrier) The open cell 1/2 pound expands 130 to 1, the two pound closed cell foam expands 30 to 1, and the 2.7 pound roof foam expands approximately 16 to 1. Open cell expands so much in a typical wall system it is typically full filled and cut off. The two pound you can control within reason. The R-value of the 1/2 pound is 3.5 per inch the two pound is approximately an R-7.0 per inch. An excellent example from SprayFoam.com (3.
Open cell is much lighter and softer being only a 1/2 pound per cubic foot. The two pound in much harder and tougher. The open cell gives you two barriers a thermal and a air barrier. The closed cell gives you four barriers, a thermal, air, moisture and vapor barrier. (Note fiberglass only gives you a thermal barrier) The open cell 1/2 pound expands 130 to 1, the two pound closed cell foam expands 30 to 1, and the 2.7 pound roof foam expands approximately 16 to 1. Open cell expands so much in a typical wall system it is typically full filled and cut off. The two pound you can control within reason. The R-value of the 1/2 pound is 3.5 per inch the two pound is approximately an R-7.0 per inch.
