Master bath [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


View Full Version : Master bath

01-08-2017, 08:25 AM
I am redoing a masterbath. I took out the pergo flooring and found it saturated underneath. Large black, wet spot at the edge of the shower. Pulled the pan and found more. Looks like the supply lines have had a slow leak for a long time. Just bought the house about 10 months ago. So far I've got the shower pan out, the separate tub, the pergo and the 1/2 particle board that was under it torn out. Looks like I'll have to pull the 3/4 osb subfloor from under the shower as well and replace it. Looking for advice on how to build it back right.

Was thinking of adding 1/2 inch ply over the osb once it is fixed. Then adding a heating mat, ditra, then some 8x20 tiles on the floor. Also thinking I want to do my first mud pan ... and advice on drain kits or systems to make it easier/better? Plan on doing kerdi for the shower enclosure

Sponsored Links

John Bridge
01-08-2017, 10:44 AM
Hi Mark, :)

For the bathroom floor, after you've added the 1/2 in ply to the 3/4 in OSB and the heat wire I would go with a tiling membrane from Schluter or from Laticrete. Then thinset and tile.

For the shower floor area, the same subfloor buildup but no heat and no membrane.

01-08-2017, 10:46 AM
Hi Mark. I'd start by going up to the blue bar above and finding the TYW store. There you will find John Bridge's Kerdi Ebook. It's well worth the 10 bucks and will help you out along the way.

01-08-2017, 11:30 AM
Thanks Mr. Bridge.

Any advice on the shower pan. I want to keep it simple, basic rectangle with a curb and shower door along one long side. A couple years ago, I thought I saw a drain kit that came with sticks to screed the mud to get the right slope. Haven't been able to find it again yet. Or is it better to just get a level line around the edge and go from there? And recommendations or warnings on a drain?

01-08-2017, 11:42 AM
Mark, I recommend you not use those plastic divider strips in your mud bed for your shower, but if you think you must have them to tell your mud where to crack, look to the left or right of this page for the Mark E advertisement.

A level line around the perimeter is the best and most efficient method of placing your mud at the correct elevation. Whatever clamping drain is convenient for you to purchase is fine to use for a traditional shower receptor. If you elect to use a direct bonded waterproofing membrane instead, you'll want the membrane manufacturer's proprietary drain.

My current favorite shower waterproofing method is the USG Durock Shower System ( All the components are available from Amazon if you don't have a local source.

My opinion; worth price charged.

01-08-2017, 08:58 PM
What works best for building the curb? Does it matter if it will be wrapped with a membrane?

Houston Remodeler
01-08-2017, 09:06 PM

We can argue over that but....

Over a ceement slab use masonry units

Over woof framing use masonry units, kiln dried wood, or kerdi board.

Our preference is 2 inch kerdi board on edge.

01-09-2017, 12:34 AM
Any advantages of the durock over kerdi, besides price? Or just personal preference? Have used rhe kerdi kit with their presloped pan before with decent results, but want to do a mud pan this time. Does the durock drain set in the mud the same way?

Houston Remodeler
01-09-2017, 09:00 AM

1 & 2- One way to look at it ; Ceement board (CBU) is kindah old school that some guys refuse to give up.

We do use cbu in steam showers just to be extra safe though.

3- Foam pans are great labor savers if everything fits the shape and size of the pan. We use drypack pans for HUGE money savings, and they fit perfectly every time.

01-09-2017, 11:35 AM
Mark, I find the Durock membrane thinner and easier to work with as well as having a lower perm rating than the Kerdi membrane. But if you like the Kerdi, no reason at all not to use it.

Durock drain installs in similar fashion to the Kerdi drain.

You can find my comments on initial testing of the product when new on this thread, mostly on pages 2 and 4. (

I agree completely with Paul on the use of mud for your shower floor rather than anyone's foam tray.

My opinion; worth price charged.

01-09-2017, 12:37 PM
Thanks to you both. Am shopping now for the durock stuff I'll need. I did a Kerri kit with their foam pan and curb last time and while it came out ok I did fight it some. Saw a durock curb, but I could by quite a few bricks for 40 bucks. Probably get the drain and a roll or two of the membrane. Worth buying the corner pieces or make my own with strips of the membrane?

01-09-2017, 01:30 PM
Unless they've changed the pre-made corners, I would not use them. Again, my information is in that link I posted.

Very easy to fold the corners with that membrane. If you have doubts, a dab of their pookey in the corners may make you feel better.

My opinion; worth price charged.

01-09-2017, 05:28 PM
Thanks CX. Was wondering, at 7 bucks a piece I can hone my origami skills.:shades:

So, does the mud pan get built directly on the wood or do I need tar paper, plastic or something under it?

Also, does the durock membrane have to go over cbu? One of the things I liked about the orange stuff was being able to go over sheetrock.

01-09-2017, 06:02 PM
You don't wanna place your deck mud directly on a wood subfloor. A cleavage membrane of poly sheeting or roofing felt with some expanded metal lath stapled over it is what you want under your sloped shower mud floor.

USG requires a CBU as backing for their shower membrane. My best guess is that the only reason for that is they don't want to spend the capital to get a code compliance waiver to allow installation over drywall. And in as much as they make both drywall and CBU it makes no difference to them which kind of product you hafta buy. If I were using it in my own house and wanted to apply it over drywall, I'd not hesitate for a moment to do so. If I were needing to meet code compliance standards, I'd use CBU. The only shower I've done with the product was installed over Durock, primarily because it was a new product test on a very public Internet site. :)

The requirement for the use of unmodified thinset mortar with the product is a "me, too" kinda requirement. They knew their competition was Schluter's Kerdi and they simply followed along with the Schluter recommendation. Were I to build a Durock Shower Membrane shower of my own and couldn't get Ditra Set, I'd be quite happy to use VersaBond both to install the membrane and to set the tiles over it. Again, if you must meet code requirements, you must follow the manufacturer's recommendations. Yes, even if you know they don't necessarily mean it. :D

My opinion; worth price charged.

01-09-2017, 08:03 PM
Thanks Cox. If Kerri can go over sheetrock, I figured this would too. Have some rebuilding to do bore I start slinging mud, but wanna make sure I got a plan.

01-12-2017, 10:47 AM
Looking back at that last post, my phone changed some words on me and it's not letting me go back and edit for some reason. Apologies, CX.

Anyway, I'm guessing the curb height and width are a matter of preference as long as it's tall enough to accommodate the height of the pan at the edge and wide enough for the door frame. Does the cleavage membrane go up and over the curb or just up the inside? If it goes up and over, do you have to cover it with lathe and at least a skim coat of the dry pack or use thinset when you wrap the waterproofing membrane over it?

01-12-2017, 12:50 PM
The membrane in your application is only for the purpose of keeping the floor from sucking the moisture out of your deck mud (see post 14). You don't need it to go over any rough curb at all. Your curb will usually be covered with whatever wall board you elect to use, then covered with the chosen waterproofing membrane.

My opinion; worth price charged.