Bathtub installation -- order of installation (end pony wall, tub, heated floor)?

Discussion in 'Shower & Bathtub Forum & Blog' started by jch, Jul 10, 2011.

  1. jch

    jch Member

    Sometimes it's super-handy having a little guy in the house who knows how to tape and mud!
  2. jch

    jch Member

    Just did the taping and mudding in the shower area. Lessons learned:

    1) Not all Fiberglas mesh tape is created equally. QEP Board Seam Tape is horrible: the glue is weak, the fabric is flimsy, and it just doesn't stay in place while thinsetting. Durock Cement Board interior tape is the opposite: sticky glue, sturdy mesh, and stays in place while thinsetting. No contest.

    2) Mapei UltraFlex LFT works great over top of Synko Concrete Fill compound. No primer needed. Stuck just as well to the con-fill as it did to the HardieBacker. Really easy to spread and feather when taping.

    3) The same rules for taping UltraFlex LFT over HardieBacker apply as with pre-mixed mud and drywall: stick the tape along the seam, press the UltraFlex LFT on thick with a 5-inch taping knife, then scrape off as much as you can on a 45 degree angle to the tape. No discernible buildup that will interfere with tiling.

    3 pounds of UltraFlex LFT did the entire wet area and gave me almost exactly an hour of working time.

    All in all, a great experience. :)
  3. dlarrivee

    dlarrivee New Member

    Sorry, I'm afraid to see the results of the mud and tape job on the drywall.
  4. jch

    jch Member

    Ah, ye have no faith in his teacher... The little guy's workmanship is much better than the contractor we let go in December...

    Here's how it looked after the little guy skimmed the far wall, and mudded the wall side of the tape on the right wall. No sanding done yet. Ceiling thinset still to be done.

    Last edited: Jul 5, 2012
  5. dlarrivee

    dlarrivee New Member

    14" of joint compound for an inside corner?

    Since you're teaching, show your kid how to hold the knife properly.

  6. johnfrwhipple

    johnfrwhipple Bathroom Design & Build - North Vancouver, B.C.

    North Vancouver, BC
    John what is this room? Is it a storage locker?

    Love the use of Child Labour! My three girls are always helping me with something. My eight year old seems to love the trades the most and my youngest six year old loves working with hardwood. She helped David and I with the face nailed floors we are installing in my home. The oldest - is all about the delegation.... lol

  7. jch

    jch Member

    Wow, tough crowd... :)

    It's tough to tell the scale from the picture but this is a 13" wide cubby in the bathroom. The mud is one 6" knife-width wide. This area will hold towels etc.

    It's not Child Labour if you don't pay them... they're apprentices... ;)

    When asked, my daughter would always say her favourite part about Grade 6 was working in the woodshop. They used to open it up during lunch to whoever wanted to use it and she and her 2 friends would go in and have the run of the place. She made some really beautiful stuff out of maple, mahogony and oak.

    My son really likes making stuff too. He keeps asking whether he can have the leftover scraps of Ditra -- not sure what he has in mind but I know it'll be cool.

    Everyone has to start somewhere...
  8. jch

    jch Member

    Trowel Sizes?

    Just about done prepping the room and finalizing the grout line placements...

    What thinsets / trowel sizes would you recommend for the following? I've linked to the product pages below in case you need to see the tile specs.

    1) Ames Radiance, 12x22" (landscape)
    - Installed over HardieBacker/AquaDefense on shower walls *and* ceiling
    - Thinking of 1/8" grout spacing
    - Would like to use LASH system
    - Considering using Mapei UltraFlex LFT White to make it easier to do the sloped ceiling -- good choice?
    - What size trowel? 3/4" square? 1/2" U? something else?

    2) Ames Sedona Marble Mosaic (Aspen), 1x2.25" Honed Marble Mosaic on 12x12" sheets
    - Installed over HardieBacker/AquaDefense on entire backsplash wall behind sink
    - Mosaics are 1/8" nominal grout line (some variation)
    - Includes some white marble(?) so am concerned about discoloration from thinset
    - Would like to use medium grey grout (matching medium stone in mosaic)
    - No idea what type of thinset to use. UltraFlex LFT White?? Something else?
    - What size trowel? 1/2" square? V-notch? Concerned about thinset squeezing up between joints

    3) Ames Fibra (Sage), 12x24" Rectified Porcelain
    - Installed on floor over Ditra
    - 1/8" grout line
    - grout colour same as #2 above (medium grey)
    - Because it's porcelain over Ditra, I'm pretty sure I have to use an unmodified thinset like Mapei Kerabond.
    - Want to use LASH system
    - What size trowel? Same as #1 above?

    The tile wholesaler won't be open when I'm doing this, so I'm hoping to get all the supplies I'll need up front.

  9. jch

    jch Member

    I called Mapei to get their opinion and here's what they recommended for thinset types and trowel sizes:

    1) 12x22" ceramic on walls & ceiling in shower over top of HardieBacker & AquaDefense:
    Mapei UltraFlex LFT
    Back-butter tiles (thin 1/32" - 1/16" layer with straight edge of trowel)
    1/4 x 3/8" square-notch trowel

    2) 1x2.25" honed marble mosaic for entire wall behind sink:
    Mapei UltraFlex LFT *White*
    3/16" V-Notch trowel

    3) 12x24" Porcelain on floor over Ditra:
    Mapei Kerabond - mixed according to package directions (add up to 5% extra water for Kerabond *under* Ditra)
    Back-butter tiles
    Try 1/4 x 3/8" square-notch trowel, but may need to move up to 1/2 x 1/2" square-notch trowel if not 100% coverage

    Hopefully this'll help someone else whose using similar sized tiles.
  10. johnfrwhipple

    johnfrwhipple Bathroom Design & Build - North Vancouver, B.C.

    North Vancouver, BC

    Great Information John.

    Thanks for sharing. You are setting the bar very high with your research. I'm sure your project will help thousands of people with question in the coming years. Well done!

  11. jch

    jch Member

    Back from vacation; just returned a whole batch of stone tile that wasn't fit for sale; and back in action.

    I've coated the shower surround area with AquaDefence, but it's so dark (dark green) that I don't know what to use to mark my tiling guidelines. Black Sharpie is invisible on this stuff!

    What do you people use to mark lines on AquaDefence when you're tiling??
  12. johnfrwhipple

    johnfrwhipple Bathroom Design & Build - North Vancouver, B.C.

    North Vancouver, BC
    Give it a scratch coat of thin-set first. This will make life easier for you. The dark colour is my only beef with the product.


  13. jch

    jch Member

    Floor is now done and grouted.
    Stone backsplash wall is now done and grouted.

    Considering using the leftover stone (0.6 x 6" stone mosaic) as a baseboard strip (a 2" high strip around the edge of the room).

    Problem is that I've already mudded (with non-setting mud) the walls. I'm concerned that thinset will dissolve the mud and the tiles will fall off.

    What can I do to provide a solid base for this thin strip of tiles along the floor?
    - Prime the walls first?
    - Paint on a narrow band of AquaDefence?
    - Something else??

    Surely this is a common problem... :confused:
  14. johnfrwhipple

    johnfrwhipple Bathroom Design & Build - North Vancouver, B.C.

    North Vancouver, BC
    Hi John.

    Lets see some progress pictures!

    If you have drywall compound on the walls already you will not get any thin-set to bite to it.

    I have been experimenting with different primers and found a good one from Mapei called Prim-Grip. I would first give the drywall a primer coat with a latex or oil based dry wall primer (paint kind) - Zissner 123 or Zissner Cover Coat my favourites. For a baseboard detail you would most likely do alright with either one but if you want an even better bond pick up a gallon of the Prim-Grip.

    The Prim-Grip has sand or something in it so stir it very well. This leaves a rough texture on the wall that thinset bites to very well.

  15. jch

    jch Member

    I agree--Zinsser 1-2-3 is my favourite primer too. I only need about 4 square feet covered and Prim-Grip's smallest can is 1 gallon so I'm going to see whether the 1-2-3 will work instead.

    In terms of updates, here we go...

    Here's the finished floor:

    Here's the finished stone backsplash wall:

    Here's the opening for the toilet flange -- a tricky cut on the saw. Even though I knew the floor would end up thick, it was shocking to actually see how thick it was in person: 3/4" T&G exterior grade plywood + 1/2" SLC (encapsulating heating wire and plastic lath) + Ditra + 3/8" Porcelain tile:

    I used a laser to keep things straight and square. The LASH clips were fine when working off a wet edge, but horrible when trying to continue the next day (I did all the field tiles first, just in case it got misaligned a bit. After 2 days, I went back and did all the edge piece cuts.) With practice, lippage became a non-issue.
  16. jch

    jch Member

    Getting closer.... Shower glass is in.


    Still to do:
    - final plumbing hookup
    - stone baseboard
    - mirror
    - frosted glass bypass doors (and shelves) in closet
    - seal grout on floor and walls (any recommendations??)
  17. johnfrwhipple

    johnfrwhipple Bathroom Design & Build - North Vancouver, B.C.

    North Vancouver, BC
    Looks like a gem John. Love the vanity
  18. jch

    jch Member

    Magick Woods Sonata, from Home Cheapo. Despite that, I like it too :)
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