Hi all, I am a carpenter in training so I'm not completely sure about this yet but to me it doesn't seem right. My grandma is having some remodels done and one thing that caught my eye today was that the contractor was using green paper drywall as his tile backer for the shower attached with drywall screws and there were 1/2" gaps between some sheets he also set the board directly on top of the plastic pan? Any insight you guys can give me would be great because I think he's starting to tile tomorrow and I wanna be able to step in before it's to late thanks!