Arlie Grunseth wrote:... I don't see where gypsum is discussed or used much by permies which makes me wonder if it might not seal off walls from water vapor on the inside just as cement stucco seals from the outside, or maybe there is another reason.
Mostly it's because people dont understand gypsum.
It's a graet material if you know how to use it. It's about the same pH as human skin, very low embodied energy as it calcines at low temp. Not so great in wet areas. It does breathe. When mixed 1:1 with Lime can achieve something like 256psi compressive strength versus gypsum or lime alone yeilding about 75psi. I could go on and on
