[Shop-talk] Covering sand textured ceiling?

[Jim Franklin]

My whole house has a sand texture ceiling- not a sprayed on coating like
popcorn, but 1/4" - 3/8" thick plaster type stuff with very coarse grit sand
on the surface. Impossible to scrape off. Also impossible to match when you
patch a hole of which I have many. So i need to cover it. Laying drywall over
it is easiest but I'd need to do a lot, plus the light holes. So I'm looking
into covering it.

Tried tonight with watered down mud and it should go in 2-3 coats. but I also
thought using actual plaster might work, and in one coat. Will plaster adhere
to this stuff? Doesn't seem to be painted and I only need 1/4" max. Or should
I just use more drywall mud? I'm decent with the technique so it won't take
forever, but I only want to do it once.

thanks,