Foam is very sticky; you'll need to wear disposable coveralls with a hood, and gloves, a face mask, and eye protection. It takes some practice to spray foam evenly and, because it expands so dramatically, to control its depth; 2 inches is all you need to seal the joist cavities. You need a clear area so that you can work without interruption; any pause longer than 30 seconds will clog the nozzle and require putting on a new one. It's also critical that the air temperature stays between 75 and 85 degrees.
Spray foam insulation or spray polyurethane foam (SPF) is an alternative to traditional building insulation such as fiberglass. A two-component mixture composed of isocyanate and polyol resin comes together at the tip of a gun, and forms an expanding foam that is sprayed onto roof tiles, concrete slabs, into wall cavities, or through holes drilled in into a cavity of a finished wall.
Excellent kit for insulating a house. Slow rising foam takes longer to insulate an area as you must do it in layers 1" thick. Any thicker can overheat the chemicals and prevent a proper cure and off-gassing. Recommend purchasing a second suit and nozzles so you can use it multiple days to achieve the thickness desired for the highest R value. Seals up and insulates much better than traditional fiberglass. The sound suppression is noticeably different. Used it to insulate the ceiling above our bedroom. The sound is remarkably more quiet than the fiberglass insulation we had before. The only down side is the weight of the containers. Using a smaller kit would be easier to handle and move around when spraying a ceiling in an attic. A word of caution, use plywood that spans at least 2 joist per container when spraying in an attic to hold the weight.
I'm in the process of redoing my basement and read through the posts. I took out one inch styrofoam covered by 1/4 " beadboard and installed 2X4s and plan on putting in fiberglass batts between them(r-13) with 1/2 in drywall over top of that. Do you think I will see a significat increase in heat control? Should I have done more?... it's a little after the fact, but still curious to know if I will see a big difference based on your experience.

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