Submitted by Ivan-Renko t3_y86elh in DIY
EDIT: I've ruled out using self-leveler period. I’ll be pulling out the current hardwoods as carefully as possible then laying new 3/4” plywood subfloor then 1/4” cement backer board before tiling. Thanks for everyone’s suggestions.
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I can't find anything online discussing the dos or don'ts of pouring self-leveling concrete directly onto hardwood flooring (NOT subfloor).
My goal is to simply retile the floor of my guest bathroom, which is 8’ x 5’. I pulled up linoleum tile, which was stuck to a sheet of vinyl flooring. Under that, I found plywood subfloor. Under that I found original hardwoods, which have their own plank subfloor. Crawlspace is below that. House was built in 1941 for reference.
The original hardwoods are in halfway decent shape other than a concrete patch running perpendicular through the center of the whole room where previous work had been done and a wall used to be. It's about 1/8" higher than the hardwoods on either side. Since my plan is to lay mosaic ceramic tile, I want to better secure the hardwoods by nailing them into the floor joists every 6-8 inches. I was then going to fill in any gaps with mortar. If I properly seal the edges and sand/prime the hardwoods, can I spread self-leveler directly onto it? Or should I put down 1/4” plywood or maybe self-adhering roofing underlayment on top first?
I'd use either concrete backerboard or ditra regardless if I were to tile.
Alternatively should I completely avoid ceramic tile since lots of sources say it’s a bad idea to put on top of wood flooring. Since the bathroom isn’t very large, I was thinking I could mitigate cracking tile/grout by using Durock or Schluter on top of the self-leveler.
Would appreciate any thoughts or advice. Thanks!!
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edited for clarity on the state of the hardwoods (pictured)
