I went through all of this. Mongoct and Bill V. are very helpful. Joist. you may or may not have the ridgidity to tile with stone. It requires a stiffer floor system than ceramic. Check the JohnBridge web site and look at their "deflectolator" to determine, roughly, your capacity. Subfloor. If you use cement board it has to be thinset inplace as well as screwed down. The thin set is not to glue in place but to fill voids that may flex and cause cracking of the tile system down the road. If you use plywood as the underlayment it needs to be screwed down on center every 6" not glued down. Ditra is a decoupleing membrain that goes down after your self leveling compound is installed. Check out my post on floor joist on the remodeling forum and here. There is a link to the remodeling forum that is very detailed and time consuming to read and interpret. I provide a link below. Check out Bill V's. post on frequently asked questions. bathroom tile FAQ's-bathrooms Check out Staceyneil's post on " Self-leveling compound & radiant heat: what I learned..." Mongoct has very detailed information throughout different posts. Here is a link that might be useful: Progress on floor prep for slate tile

One post mentioned if I install on top of the plywood, there needs to be a layer of thinset under the mesh..is this the same thing as putting the mat on the plywood, and then troweling on thinset? Or do I need to put a layer on first and let that dry, and then attach the mesh with another layer of thinset? The only system I know of that needs to have thinset under the system before you put it down over the plywood Nuheat. You need to trowel down fresh thinset, lay in the mat (which is basically the same mesh as cheesecloth with the wire running thru it), and then thinset over the top, so that the mat is basically sandwiched in the fresh thinset. I'm not Mongo, but I'll answer anyway. A wet room is a bathroom where the entire floor is waterproofed so that no curb is needed for the shower. It's basically for handicapped showers, and the entire bathroom floor is more or less the shower pan. Is anything bathroom a wet room. Usually only the shower. Is Ditra overkill for a bathroom floor If you don't have a movement problem, or if you don't need to knoch the height down that extra 1/8" that the Ditra gives you in place of cement board, then 1/4" cement board should more than suffice for most ceramic jobs.

On Wed, Aug 5, 2009 at 3:43 PM, barredrock <....> wrote: [This message originated at GardenWeb] thanks for your input so far. this is what im doing now on the bathroom floor, see what you think so this is what im thinking. in this order, tell me what i am or aint doing right thanks 1. I believe it is 5/8 tongue and groove osb 2. 1/4 inch hardibacker 3. suntouch heated floor mat embedded in modified thinset and let dry how long before applying tile? 4. Do i need a leveler???? 5. ditra with unmodified thinset on both sides 6. tile ------------------------------------------ Answers Step Zero is missing. Step 1 is not enough. Step 2 is good. With expensive screws. Step 3 is good. Depends on the instructions on the bag. E.g. eighteen hours or so. Step 4 not unless you think you need it. Are these humungous tiles or puny tiles? Do you have a 6' level and what does it look like when laid on the floor in various directions? With thinset you can compensate easily up to a point.... but that all depends. Step 5 may be unnecessary, but it depends on Step 1 and Step Zero (what joists you have) Ditra is good for slabs that may crack a bit and widen horizontally. It might help also on Hardibacker or any other CBU on wood. But this has been debated a lot and never "proven" a.f.a.i.k. If your floor is springy, Ditra won't compensate enough to make it worthwhile. Step 6 what size is your tile? Have you tiled before? Do you know what slaking is? Etcetera... -- David

The rubber cement (or rubber something, I can't remember, so I thought it's rubber cement) is used to patch the existing concrete cracks, then will use leveling compound to level/flatten the floor. Then thinset, the membrane, then thinset and the tile. But my question remains, even if I don't use this contractor, I need to know if the Schluter Ditra is good for my situation and what's the potential installation problems I need to look out for when selecting contractors. Thanks, May