Couldn't find a more recent thread on the subject, so here's a new one, even though it looks like this comes up regularly.
Specifically, I want to use thinset mortar to patch screw holes and cracks in a new bathroom underlayment before putting down a one piece vinyl floor.
Yeah, I know there's a lot wrong with that statement. This is for a cheap, quick and dirty bathroom tear out. I am running out of money and my main concern is doing a serviceable job that can be easily torn out and redone should the funds and inclination arise.
Tore out several layers of vinyl and tile flooring and some rotten joists and pieces of subfloor and replaced them with new plywood. Not many pieces, so everything's pretty uniform and flush.
Want to use thinset to patch already level underlayment so the flooring doesn't pit with wear and tear. Going to cover it with vinyl floor adhesive and floor.
Does that sound reasonable? There's no kind of chemical interaction or wear and tear reason not to have sanded thinset under that kind of floor?
I do get that. I guess my main reason for wanting to use thinset is because I have a half a bag left over from doing the walls and really don't want to pay for and store more stuff if I don't have to.
The room was torn out down to the frame and rebuilt on the absolute cheap with an eye to redoing when as finances allow -- good walls and subfloor but mostly cheap-azz finishing that will last till I can get the place refinanced and free up money to do sturdy repairs.
And "sturdy" is kind of a relative term. The house is a teeny 1960s cracker-box in a neighborhood where it won't ever be worth more than $80K or so. It's a home, not an investment or flip material.