I'm seeing a ton of waterproofing posts here lately leading people to believe they're going to have to tear out entire bathrooms because redguard wasn't applied. We need to set the record straight here and I'm sure a lot of you aren't going to like it.

Is waterproofing a good idea? YES, ABSOLUTELY. Water damage is a nightmare to deal with and you as the customer are better off having it and you as the contractor are better off talking the customer into upgrading to it if it's not required by code.

Is waterproofing necessary? NO/MAYBE, CHECK YOUR CODE AND MANUFACTURER RECOMMENDATIONS FOR YOUR MATERIALS. A full Durock shower encloser, using proper hardware, tape, joint sealer, a correctly installed pan, modified thinset and ceramic tile will result in a shower that has no moisture issues.

How do I know this? I've helped install these showers for decades in Florida and have never once had an issue (we keep in touch with our clients and have even redone the same bathrooms years later because they wanted upgrades). We have also used Schluter systems and redguard and advocated for that. But if the client doesn't want to spend the money, not using a waterproofing barrier is perfectly acceptable based on code and will not cause any harm. I've torn out showers from the 1980s that had none of the materials we use today and found little to no moisture problems.

So let's cut down on the panic when homeowners post here and try to give them the facts. Otherwise we are leading them to spend way more money than necessary and are creating a nightmare of a client do deal with for good contractors*.

*Most of the stuff posted here is not done by good contractors and waterproofing is the least of your worries.

Edit: I figured I'd get down voted but I'm literally quoting code for my area and manufacturer instructions for the product I mentioned.

I'm not talking about drywall, greenboard, purple board or any other gypsum based product which require a barrier.

I’ve used Durock for the shower walls and will use alkali-resistant tape and mortar on the joints. I plan to use Mapei Aqua Defense on all walls. Is it necessary to use liquid membrane banding over the alki-resistant tape? Seems like overkill but it seems to be what the manufacturer recommends.