Is spray foam insulation safe to use in a ceiling against the roof decking framing, or is it likely to cause rot and disintegration?
Asked by Tracy Herrera 
4 months ago
Last Updated: August 5, 2024
Hey, do you think it’s a good idea to use spray foam insulation in the ceiling against the roof decking and framing? I’ve heard some scary stories about it potentially causing the roof to rot or disintegrate.
I haven’t observed any roofs deteriorating faster with spray foam. Roofing is part of my business. I have it installed throughout my house, including cathedral ceilings.
The horror story only happens if the roof leaks and the homeowner can’t see water staining. Roof sheathing can also retain water and eventually decay if it can’t dry properly. Personally, I’m not a fan. Use Rockwool instead 👍