Spray Foam Basics: Consistency Is Everything For anyone learning spray foam, this is where it starts: consistency and flow. Spray foam works a lot like painting smooth, even passes matter. Stay on it too long when the foam is hot and it overreacts. Too cold, and it won’t react fast enough and can sag or run. Getting the temperature, pace, and flow right is what separates a clean install from a messy one. There’s more than one way to spray a cavity. Some techs picture-frame, others can run full p