I don't believe it is, although I have used it myself in small amounts over showers and whatnot. This is just something i've read online, however it seemed true.
I would never use green board in a "wet area" as in a tiled area around a shower. However I do believe that reguar drywall ...
You may not want to use greenboard for your ceiling in the main part of your bathroom. I don't believe it is rated for horizontal application, that is what i've read anyways. Apparently it does not have the same holding strength overhead for 16'' centres, you may be ok to go with furring...
another option that I see used most frequently for getting rid of a popcorn ceiling for a flat look-
Scrape the popcorn off, use water lightly to help. 2 skimcoats of drywall compound over the whole area, good sand, prime and paint.
If you want a "dummy door" you may want to put a sheet of doorskin up and use it as a jig, never done this however I have heard of it being done.
another way would be to get a helper and place the door in the opening, marking where it may need to be cut/planed, as well where hinges would go...
Just get other estimates if you aren't confident, compare them and go with the one you feel comfortable with.
As mentioned it is best to get written quotes, with a scope of work. That way everyone knows what will be done for what price.
Hello all, just came across the site and signed up. I am a carpenter from Vancouver BC, with a small home improvement business.
Looking forward to learning new things and giving advice..