New home bathroom construction
 

Way off the outdoors topic, but I’m wondering if there any GC’s or knowledgeable people here caught up on current code. What’s required to go behind a fibreglass tub surround? In my mind I’m picturing either cement board with membrane, or aquarboard as a minimum?

Asking for a friend lol

I'm not a contractor, a trade or even knowledgeable :) but if code calls for more than water resistant drywall behind a fiberglass surround, I give up...

ARG

No one ever regretted extra waterproofing of any variety around any type of fixture that holds water. It won’t be that expensive in the grand scheme.

I’m just a hack, so take what I say with a grain of salt.

Aqua board is crap, "water resistant", spend the little bit extra up front, rather than go back to deal with a problem later. Talking as a guy who built a lot of bath rooms. Several options, not really difficult to work with.

Grizz

I didn’t want to start a hissing match with someone who may like aqua board, but my limited experience in our first two homes would cause me to agree with you.

Not looking for a match of any sort, just trying to chase code without actually chasing code, cause definitely going to upset people either way. I feel on a new build that waterproofing needs and should be done. But said “friend” was told that “paint is enough of a vapour barrier” by his or hers GC.

I’m just a stupid furnace guy here, so even though I think better is needed, I don’t know the code

Generally the hardwall fiberglass tub surrounds screw right to the studs with no wall board behind it.

I am going to assume you are in Calgary. Just phone the city building inspector and ask.

Code and best practices depend on if there are any exterior walls as part of the tub enclosure. Water proofing membrane on the inside of an exterior wall is not a good idea as you’re trapping material between it and Vapor barrier.