I wonder if our GC's proposal is overkill. We've just installed new PEX radiant heat panels over existing slab on grade, and now are considering having tile rather than 5/8" engineered wood above the radiant panels (Rehau Raupanel, 8" OC). The Raupanel installation specs diagram for tile installation shows the following layers: - ceramic tile (1/4" typical) - cement or mortar compound w/ mesh or rubber membrane (1/4" typical) [e.g. Schulter Ditra?] - Raupanel + PEX + furring strips - vapor barrier - concrete slab Our GC claims we need to: -tear out the Raupanel and furring strips. -have loops of Pex with a concrete overpour, -then plywood base, a 1/2" backerboard, - and finally the tile in thinset (I think). What's going on? I think the GC said this is for sufficient isolation from expansion, and the tear-out needed to keep the assembly from being almost 1" higher than the adjacent room (5/8" Owens Plankfloor above Raupanel). But some of the GC's solutions have been un-nece$$arily labor-inten$ive, so I've become alert to padded proposals. BTW, His partial quote, for the 50 sq ft room is: "Demo the existing wood furring strips and float the floor and install the owner provided tile. Total cost 2,100.00 (Note the base will be wood provided in an alternate price)" Does that make sense? What should I do next? ------ PS. Should we even be doing tile, vs. e.g., linoleum, if we may have a litter-box and/or pet food bowls in the room? I started imagining urine odor in grout....

Since gypsum melts in water, I would only do a dry shampoo.

@Millworkman Thanks. That thought about adding another layer (and maybe getting less heat) did cross my mind. I'm not too concerned about it though as we cook a lot and are generally hot natured people (we keep our heat pretty low in the winter). Plus the kitchen is fairly small (less than 200 square feet and that includes a broom closet and small walk in pantry). I'm sure the proper way to do it would be to rip it all out but I worry about damaging the heating system. Is a little heat better than the risk of no heat? Ha!

Hoping someone can give us an answer. We are wanting to replace our 50-year-old Saltillo tile floor. There are MANY reasons, and I know they appear good but they’re not. Here’s the issue, our home is heated by radiant heat, hydronic, in the slab underneath. We’ve been told by one flooring contractor that the Saltillo HAS to be demoed. Another said not at all a problem to float an LVP floor over the Saltillo tile. The tile is very uneven and many are cracked. Is there anyone out there who has experience with this that can advise re taking floor out or floating over? Will the heat still be able to conduct if we go over?? THANKS for any advice.