Leaving rockwool exposed in basement ceiling
Hi. A few places in my basement ceiling cannot be finished with sheetrock: above the electrical panel, the concrete block wall behind the boiler, etc, due to too many pipes or electrical conduits converging. Yet I still need to maintain a fire-rated ceiling in those locations. The building inspector suggested I pack those locations with rock wool.
How can I do this and not have an eternal sprinkle of rockwool fibers raining down on me under these locations? Just curious what other people have done.
One thought that comes to mind is to spray the rockwool with a clear-coat spraypaint sealer after it’s installed, just to try to make a surface that binds the fibers together a little, but that’s probably not compatible with the whole fire-rated ceiling theory.
Advice appreciated.
Theodore
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Replies
Theodore,
Have you looked into rock wool boards like Roxul Comfortboard? They may have stopped that particular product name, but the boards are much more ridge and would really only be friable if you were messing with them.
I have not dealt with rock wool batts, but the boards are pretty sturdy and have stood up outside well, even without covering while I finish installing them.
Hi. I know the product you're speaking of, but it won't help in my case. I'm trying to fire-block up and behind these cables (see arrow call-out). A rigid board won't do, as it won't fit. I (supposedly) need to stuff pieces of rockwool up into this area. That's why I'm concerned about the perpetual friability, especially over my boiler, where all that dust can't be good for my burner over time.
Theodore,
Install furring, blocking, and shims where necessary, and cover the wires with drywall. It won't look any worse thant leaving the wires exposed if some of the drywall is proud of the main plane of the wall in a few areas.