Please don't use spray foam. That stuff will make your eyes burn and give you rash for months after, and make you sensitive to future exposure. It's isocyanate, read up. Also, it burns hot and fast and is easily ignited, producing cyanide in the choking dense smoke while it burns. Look that up, too. I don't know why it's even legal, for all the people it's put in the hospital and in the ground. Yes, you can read that stuff too! Batts work, they damp sound, and glass fiber doesn't absorb moisture or catch fire. All good reasons to use it instead. I sure did. My shop doesn't leak noise to bother the neighbors and doesn't irritate my mucous membranes from offgassing toxic carp.