put the mortar bed directly on fresh slightly runny modified thinset. If it takes you a while to get going you may have to re-trowel the thinset periodically to keep it from skinning over.

Jill,

As Pete said the point of the thinset is to bond the deck mud to the concrete, so mud over fresh thinset.

If YOU or anyone else reading this has a question that needs further clarification, You may call my mobile at 248-670-3967. Don't worry, I have several thousand roll-over minutes that I should use up.

Jaz

Ok here's an update, we did the preslope on saturday and it went well. Thanks to all of you of course! Today tho I noticed that there was some sand on the top of my mud bed. I started sweeping and ended up with a pretty good pile of sand! Is this normal? If not what do I do now? ( Don't say tear it out and start over please!! )

We are eager to get started with the membrane phase but want to make sure this is going to be ok.

Thanks for all the help!!!


Jill

The pre-slope sounds fine, and it really doesn't matter that much anyway. So go ahead with the membrane. Are you going to fir-out the studs to allow for the thickness of the folded membrane, or what are your plans? What kind of backer are you using? How are you building the curb?

Jaz

Whew! I sure am glad to hear that! The membrane folding part was my next question. If we fir the studs then add the wonderboard how do i compensate for the difference to the original drywall outside the shower?

As far as the curb, we have 4 stacked 2x4s and are going to use metal lath over it.

Jill

Here are questions for the future of the shower building experiment:

Should we use a vapor barrier behind the cbu or just redguard it all?

Use white thinset, gray thinset, or mastic for the shower tiles?

We want to tile over the existing marble floor in the bathroom, will regular or modified thinset do the job or is there a better way?

I really want to thank you all for your help! You have no idea how much you've helped
out!!!

Jill

Harry has some very nice articles about this right here. Go to the home page and read away. http://www.ontariotile.com/

Shim about 1/4" use lattice or ?. You'll have an extra 1/4" of grout is all. If you can find "mud cap" (A4200) to match your tiles, you can shim out 1/2" and use the mud caps to return back to the wallboard.

Curb, 4 2x4's are ok. I use 3 but?

Surface membrane is much better than the other method. So use Redguard or Hydro Ban unless you go with Kerdi shower.

I would use white thinset. Do NOT say the "M" word around professional. It is no good for wet areas. And NEVER on floors.

Scuff up the marble with ruff paper if it's in perfect condition and no hairline cracks in the grout. Use white modified thinset just like in the shower. What tiles are you using anyway? Shower walls, floor and bath floor?

Jaz

white thinset is always used with marble, glass tile, and sometimes used with light colored grouts to avoid any chance of ghosting. everything else can be done with gray thinset.

If you are going to use Redgard, then you don't need cement board, just drywall.

if the walls are not load bearing you can notch out the studs to accommodate the liner folds. If you fur out 1/8 th or 1/4 you can run the tiles a little bit past the drywall transition and use a thicker Schluter tile edge.

Thanks Jaz and pistolpete! I didn't know you could use drywall and just redguard it I thought you had to use cbu. Lucky for us we have some greenboard in the garage now we can put to use.

We are using 12x12 tiles on everything I think. We've been talking about using bigger tile on the bathroom floor but haven't decided.

Well we are off on vacation starting tomorrow so no work will get accomplished until next weekend when we get back.

Thanks again and I will read those articles on the home page when I get back for sure!

Jill

the shower pan itself should be a 2x2 or smaller mosaic.