Exposed batt insulation, no dusting
I have (I think) 10 or 11 joist bays in a utility area in my basement. The joist bays are pretty populated with duct runs, power+data, PEX plumbing, etc with some of those running perpendicular across the bottom of the joists, making a hard lid almost impossible. Besides, I like having access to everything in this area (below the kitchen).
However, it’s a bit noisy (both ways) whether the kitchen traffic coming down or the utility room (furnace, my ‘mini shop’) sound going up.
I am thinking about insulating the top 3rd (up against the T&G d.fir sheeting of the kitchen floor) to help attenuate sound a bit. Joists are true 2×10. The bays are maybe 12ft long each (some shorter) so I don’t need a ton of product, but I am not certain I can work around everything in the joists with long rolls of fiberglass batts (w/o driving myself crazy and tearing the kraft paper constantly). I use roxul a lot and I like that idea, but I notice that when it’s uncovered it can dust a bit and would drop fibers and things over the years.
Any other ideas? Denim batts (seems like that would dust as well over time). Maybe just small sections of kraft-backed R13 pink fluff and some staples to keep it up? Again, I got a feeling I’ll be going crazy trying to work around everything.
Thanks
S
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Sean,
I don't think your plan will result in a significant reduction in sound transmission. If you really want to reduce sound transmission, you'll have to look at solutions that include a pad and carpet upstairs, or heavy drywall mounted on "sound clips" attached to the underside of the joists (plus fiberglass batts or mineral wool batts, of course).
It's not going to be the best, I understand - but a little should help. I'll try with some cheap kraft backed batts (use what I have leftover) and see if that helps at all.