Acoustic treatment for a garage ceiling

so, is this going to be a drive-in home theater? if the ceiling is as hard surfaced as the walls, i'd recommend putting up at least a few (black) sonex squares. they often work better on ceilings than walls. -cfb

Have the ceiling sprayed with cellulose insulation fiber. This will deaden slap-echo & will also help insulate against heat gain/loss & attenuate outside noises from getting in. You'll often see gray cellulose fiber sprayed on warehouse ceilings & walls; usually several inches thick. It is also available in bleached white, which is what I had applied on my listening room ceiling with excellent acoustic results. See an insulation contractor for details & ask about mixing in some black paint or dye with the glue before they apply it. Be aware that this is a messy job so mask accordingly.

Thanks, Bob. I'll suggest that my buddy call a contractor.

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