Exposed insulation

[Myles Moran]

I have a basement shop. I put some mineral wool up in the finished portion (above a drop ceiling) and have been very happy with the results for sound transfer reduction (important for any room housing guitar amps and a drum kit). Now I'm considering doing the rest of the basement, aka the shop and a storage closet.

Exposed insulation in the storage area doesn't seem much of an issue, we keep most stuff in totes and don't every touch the ceiling. Seems easy enough to insulate and leave it held in place with the steel rods sold for that use.

My question is primarily focused at the shop area. I've been known to be a little careless and bump the ceiling (well the ductwork more) with a piece of rough lumber. Sawdust getting stuck up there comes to mind. But at the same time this area houses all the ductwork dampers I adjust for heating/cooling season, and has all sorts of conduit and other stuff popping in and out of the ceiling for various machines.

My question is: does anyone have exposed insulation in their shop? Would you recommend covering the insulation with something? (While maintaining access to duct dampers, junction boxes, and all similar.) Is quieting the house up from the shop noises worth it?

[Aaron Inami]

If the insulation is away from hands and anything that can scrape it, then I think it's relatively safe. Mineral wool panels will have a tendency to sage, so I would not recommend it if you don't have any supporting frame or cross members. The fiberglass stuff like Owens 703 would be better because it stays stiff even when hanging or leaning.

[Jim Becker]

Some kind of simple mesh would insure it stays in place, still has the same sound properties and will allow access to infrastructure if absolutely necessary. It could even be runs of string at intervals that are stapled to the joists.

[Myles Moran]

Mineral wool panels will have a tendency to sage, so I would not recommend it if you don't have any supporting frame or cross members.

I learned this one the hard way. The premium mineral wool products are what make the marketing photos. The stuff I can buy at the box store is basically extra-heavy fiberglass batts. Luckily I bought double the supports I thought I would need so it should be well supported.

Edit- Jim- how fine of a mesh would you use? I supported the insulation with the spring steel supports to keep it tucked up to the sub floor above, so if I install correctly I shouldn't have sag issues. It would be a good inexpensive material to protect everything in the joist bays.

[Bill Dufour]

Chicken wire is cheap enough. Or get some steel concrete tie wire and weave it around between nails. Same as lacing a turkey with pins.
Exposed fiberglass is a fire hazard. Mineral wool is not unless it is coated in sawdust.
BilL D

https://www.homedepot.com/p/Weyerhaeuser-400-ft-16-5-Gauge-Rebar-Tie-Wire-05337/202094311

[Ron Selzer]

"Exposed fiberglass is a fire hazard. "

Where did you get this information at? Fiberglass insulation does not burn, IF it has a facing, that might burn the fiberglass does not burn. Take a torch and hold it on fiberglass, it will not ignite or burn.
Ron

[George Yetka]

I would cover it. Every time someone walks over you a little bit will come down and into your lungs. If it were paper backed you may be OK

[Jim Becker]

Inexpensive canvas drop cloths are another idea that doesn't mess with the sound abatement.

Myles, if you bought mineral wool, the color and texture should clearly differentiate it from fiberglass. Rockwool, Roxul, Thermafiber, etc., are all products that do not resemble fiberglass insulation at all. Even the "sound abatement" version of Rockwool is the same greenish brown color as their insulation versions. Mineral wool is pretty self supporting, too, as it's fairly ridgid, even in the sound abatement version. It's never "fluffy".

[Aaron Inami]

The mineral wool products like Roxul AFB are flexible batts that can break apart in your hand when handling. The heavier mineral wool products like Roxul Rockboard or Comfortboard are very stiff and heavy, but they will still sag over time unless you support it with a frame/fabric or crossmember (just a couple of thin piece of wood is fine). The fiberglass products like Owens 703 are stiff and light and will not sag at all.

Here's a good page showing comparisons and weight (per cubic feet of material):

https://www.atsacoustics.com/page--Selecting-the-Right-Acoustic-Material--ac.html

[Myles Moran]

Yes, that roxul AFB photo really captures it. It's definitely different from fiberglass, I could pick up a batt and it held it's shape fairly well, but if I wasn't careful installing it, it would end up snapping in half. I wouldn't describe it as fluffy, but rather the little bits hanging off want to fall off and get airborne like fiberglass does. But overall it is much denser and far less compressible.

[Mel Fulks]

I used Roxul once ,mainly for sound -proofing. Yes ,it’s dense . It can break , “ handle with care “ …. makes for a nice quiet
bathroom …. but probably not up to current HI- Fidelity standards.

[Bill Dufour]

As. kid I packed pink fiberglass insulation into pipe to make a muffler. with the lawnmower engine running it quickly smoked and bits of pure white glass blew out. All the glue and pink dye burned up leaving pure white glass fibers behind.
Bill D.

Watch at 1:25
https://www.youtube.com/watch?v=4velkAFJRwM

[Lee Schierer]

Be sure you don't cover any junction boxes when you put in the insulation, they need to remain accessible and visible.