Shower ripped out, base was cracked. Figured out why, they drain install was done by someone who didn't have a clue. Water made it out under the pan and rotted the planks over the joists. SO i've removed the planks 3/4 inch, will be sistering some new joists up to strengthen the floor for tile. Plan on using https://www.schluter.com/schluter-us/en_US/Shower-System/Waterproofing/c/SS-W for the shower and their membrane over the floor and under the tile. Question is, should I use a pressure treated 6 or 8 inch wide 3/4 like https://www.homedepot.com/p/WeatherShield-1-in-x-4-in-x-8-ft-Pressure-Treated-Board-155395/100074805 Or pressure treated plywood? OR ??? what. They had linoleum, with the schluter system and tile I will create transition between the bathroom and the master bedroom. Would like to keep that to a minimum. Want to do it right and NOT have the tile crack or ever have to revisit this nor have issues with a future home inspector.
