On one hand it could just be cement board, but it may also be asbestos containing cement board - as others have said, until you test it, there’s literally no way of knowing.
Either way, cutting it with a grinder is fucking stupid and messy as fuck (but also how everyone does it and I’m not sure what the alternative is). Inhaling any of that dust is a bad idea.
You can get asbestos self test kits with a fast turn around, but not sure where you’d collect a sample from if they’ve packed up and gone.
Some are reinforced with some sort of stranded grid though aren’t they? Although probably not something you’d have to board a garage ceiling. I’m out my depth at this point!
On one hand it could just be cement board, but it may also be asbestos containing cement board - as others have said, until you test it, there’s literally no way of knowing.
Either way, cutting it with a grinder is fucking stupid and messy as fuck (but also how everyone does it and I’m not sure what the alternative is). Inhaling any of that dust is a bad idea.
You can get asbestos self test kits with a fast turn around, but not sure where you’d collect a sample from if they’ve packed up and gone.