Unknown Insulation?
Hello All, I have been doing Energy Audits in upstate NY for almost 8 years and am rarely stumped but this ones got me.. I was doing an audit on a 1930’s Bungalow and just cannot figure out what type of insulation this is/was.
It was a white powdery substance that had some sort of fibers mixed in with it. It almost looked like fiberglass mixed with flour. It was pretty much filling the ceiling joists in the attic, My only assumption is it may be a form of poly urea foam that has completely broken down to just dust (normally it still has some shape to it until touched) but maybe when they layed additional fiberglass over it that’s what happened?
The owner said he was concerned when purchasing the house and said they had it tested and it did come back as NOT asbestos containing. None the less i op’ed to not doing the blower door.
I’m stumped any ideas?
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My guess would be urea-formaldehyde foam insulation, though I have only previously seen it in wall cavities and it did not have any fibers in it. In the applications I have seen it has degraded into basically a powder, expecially when disturbed.
I don't have any idea what that is, but it is extraordinarily unlikely that a residential loose fill insulation other than vermiculite contains asbestos.