Replies

1. 
   davidmeiland | Mar 30, 2004 09:49am | #1

   You need to float mud over the curb. You can't put fasteners through the membrane. No wonderboard...

   Best thing to do is buy Michael Byrne's book 'Setting Tile' and study the shower chapter.

1. 
   CloudHidden | Mar 30, 2004 04:02pm | #2

   You can get pre-formed curbs, too. They are u-shaped and slide over the curb framing and liner and serve as a tile base. Bonsal makes them--$80 or so, I think--among others.

2. 
   planefrog | Mar 30, 2004 05:04pm | #3

   Thanks for the advice, I knew I shouldn't put fasteners in the curb and that's what puzzled me. Now how thick do I make it? It can't be to thin or it will flex and break. An inch enough?

1. 
   WorkshopJon | Mar 30, 2004 05:24pm | #4

   Frog,

   I know there are a few ways to do this, but to create a ledge to strike off to establish the slope for the floor, I've had good luck with imbedding strips of CBU that I ripped up around the perimeter.  Also heard of people using wood, then removing it and filling in the void, but that is an extra step.

   Jon

2. 
   Scooter1 | Mar 30, 2004 06:30pm | #5

   Once your membrane is done, finish out the walls down to the membrane, but hold off the membrane about a quarter inch from the sloped membrane. Your membrane is sloped, right??? Please say yes.

   The wall backerboard will, as one poster suggested, act as a screed for the curb. Thus the curb mud will be about a half an inch thick.

   Get some diamond lathe and fold it into a U shaped channel, a tad tighter than your curb. Fit it over the curb and hopefully because it was a very tight fit, it will fit very snug over the curb. Nail it to the curb on the outside only. Mix up some mud with lime in it called "Wall Float". You can get it pre-bagged at the masonry supplier or DalTile. If you can't find it mix up your own by adding 6 scoops of sand, 1 scoop of portland cement and one half scoop of lime. Or add a scoop of lime to "Deck Mud" or "Dry Pack", which is also a pre-bagged product.

   Mix the stuff fairly dry and smear it on the inside of the curb with a margin trowel. Be generous and pack it in nicely. Use a straight edge over the CBU's to act as a screed, seesawing back and forth up the curb. Do the outside the same way. For the top, smear any thickness onto the curb over a half inch or so, it doesn't matter. Take a 1x6 board and put it on top of the curb and smoosh it down, and angle the board to the inside of the shower. You want the top of the curb pitched about a sixteenth or so, about a half a bubble.

   Clean up the edges with a flat trowel, make it look pretty and you are done.

   Regards,

   Boris

   "Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934