Rockwool attic insulation
GreenHomeowner
| Posted in General Questions on
We are going to be air-sealing and supplementing the insulation in the attic of our 1960s home. It currently has a thin layer of rockwool and cellulose. One contractor we spoke to encouraged us to have the existing insulation removed due to the the rockwool from that era being dangerous to breathe. Removing the existing insulation would, of course, add significant expense to the project. Any thoughts on the safety of 1960s rockwool insulation?
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Replies
I’m not aware of any safety issues with old mineral wool. Was your contractor perhaps thinking of vermiculite instead? Old vermiculite sometimes contains asbestos, and that can be a problem.
Bill
It could be that the contractor is thinking about mineral wool binders, which can contain formaldehyde. This article might be of interest: Mineral Wool Makers Dropping Formaldehyde Binders.
Thank you both for your input!