Closed cell form excels at being attic insulation, as it provides an average R-value of 6 per inch of thickness via an insulating gas inside the cells. This durable foam type is an excellent barrier to both moisture and air. In fact, when sprayed it provides support to the frame of your home! In addition this foam can be sprayed into tight areas that might be impossible to reach.
Closed cell foam excels when used for interior and exterior locations, walls (including knee), attic floors, and crawlspaces.