Plaster VS. Moisture Resistant Drywall
user-2423385
| Posted in General Questions on
Hey gang,
Were getting to finishing insulation (cut and cobble is a ton of work and beginning to believe it’s only worth it if you have much more time than money) and starting to put in the finish walls. I’m going to use blue board and a two part plaster system for most of the walls and ceilings. What are your opinions for using the plaster system in high moisture areas vs the use of moisture resistant drywall? Thanks much for all your help.
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No ideas on this?
by two part, I assume you mean a brown coat like Structolite, and a 2nd brown coat or a lime coat for a total of 3/8"? That works great pretty much everywhere. Ours is in perfect condition after 30 years.
You've read Martin's article on cut and cobble.... right?
https://www.greenbuildingadvisor.com/blogs/dept/musings/cut-and-cobble-insulation
Blue board still has paper in it correct? Stuff with paper can feed molds... if you are thinking high moisture areas.... do you have mold conditions present?
The topic was brought up a couple of years ago...
https://www.greenbuildingadvisor.com/community/forum/green-products-and-materials/18396/should-we-use-fiberglass-blue-board
Yes I have read the article. I do have 3" of XPS in between the joists (balloon frame with 1" TNG sheathing with soon to be simply tar paper then cedar shingles on the exterior). The XPS is fully sealed with spray foam (200 cans) and then there is an additional 3-5" of cellulose/mooney walls in the interior. I can't imagine the benefit of using "drywall" vs using a blue-board and plaster approach. The interior on every wall with the XPS is treated with a "vapor barrier" paint vs poly which the inspectors wanted but allowed the paint as long as we saved the labels. Yes...Paper can create mold but as long as there is either lots of air...or very little air it shouldn't be a problem, if moisture is controlled. The hundreds of 1800's newspapers that were stuffed in the walls
I have attest to that.