I am installing a graded mud floor in a commercial bathroom, on a slab. It needs a 3/4″ gradient from the wall to the drain. I am using 12″x12″ tiles. Should I lay a layer of lath and tar paper down before setting the tiles? Or just pour the bud down and hope for the best?
Any help is appreciated..
Mark
Performance improvements for the prized homes of an influential developer who wanted us all to be able to own one.
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Replies
How much does this project matter?? It sounds like a job for an experienced tilesetter, and it doesn't sound like you are one, or at least not with mortar beds.
Suggest you buy and read "Setting Tile" by Michael Byrne, and also buy the TCA handbook.
Wow, you got slammed.
I don't have the space here to tell you how to float a sloped mud bed. But you are going to have to make screeds of pipe or mud which match the slope spec'ed in your design. So the end of the screed by the drain will be 3/4 of an inch lower than by the wall.
You can do that with a level string line or a laser level.
The screens will fan out like spokes on a wheel to the edge of the wall. If one spoke is a tad longer than another (not uncommon in a square room) then the perimeter has to all be the same, so you will have to snap a level line along the perimeter. The distance between the farthest point on that spoke to the drain should drop 3/4". The shorter ones will obviously have a steeper slope but the perimeter must remain level or the job will really look screwy.
Mud is mixed 6 parts sand to 1 part portland or buy the pre-mixed dry pack, and only add enough water to make it barely moist. Pack it down tight with a wooden float and strike it off against the screeds with a straight edge.
Ditto on Mike Byrnes book or John Bridge's book, too.
Regards,
Scooter
"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
Maybe I was harsh, but it always bums me out when a tradesperson says 'I'll just do "X" and hope for the best'. You should know with at least some certainty that what you're going to do will work. Floating mud is one of those things that's best learned while you're a helper and someone else is running the show.
I was not criticizing you. I often give smug answers to stupid questions. My favorite are I am rewiring my panel, the little white wires seem to terminate in a little thingy that has the green wires connected to it, too. Is that OK?I just happened to be in a generous mood today, David. No offense meant.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
None whatsoever taken. I think maybe I'm sensitive today from the thread where a guy focked up an entire house with cedar shingles. It makes us all look like shid.
Yea, the floor is currently being done by a "Professional" Tile guy "Johnny Tile". I was on-site yesterday and he is just using thinset to grade the floor. I Agree that if you dont do it correctly that you shouldnt do it at all. But, it is being done anyway (I am protesting the pro's continued employment).Now, I am in a position where I may do a better job than the "Pro" on this project. The graded floor is already done so all i need to do is the field tile. I have that one under control. I am a floating PM on this project and not responsible for the finished outcome but I am interested in getting it back on track. I just dont want our company to look bad. Company Man... Thanks for the help guys Mark