What to put on top of slab insulation in the bathroom?
mattseab
| Posted in Energy Efficiency and Durability on
I previously asked about insulating my existing slab and am underway with the project; 3/4″ rigid foam, 2 layers of floating plywood with the first 3/4″ and second layer 1/2″. My question is what to do in the bathroom where tile will be the finish floor? Is one layer of 1/2″ durock on top of the insulation adequate? Should I double it and lay the second layer perpendicular attached via backerboard screws? I just want to make sure it’s stable before the tile is laid. Thanks
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Replies
Matthew,
You need at least two layers under ceramic tile. If you are installing 3/4 inch plywood plus 1/2 inch plywood everywhere else, then you want at least 34 inch plywood and 1/2 inch Durock under the ceramic tile. But you should confirm these details with your tile installer before proceeding.