You have it way backwards.

You need to do some reasearch.

1.) Thisnset
2.Backerboard
3.Screws
4.Thinset
5.) Heating Pad(on top of wet thinset, let it dry then lay tile like
normal)
6.)Thinset
7.)Tile

You'll use easy mat or 1/4 inch hardbacker not 1/2 inch


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