(206) 949-5683, Top Rated Plumber, Seattle
Page 2 of 4 FirstFirst 1234 LastLast
Results 16 to 30 of 48

Thread: Schluter Shower install - wicking issue

  1. #16
    DIY Junior Member keithterry's Avatar
    Join Date
    Oct 2013
    Location
    Ohio
    Posts
    14

    Default

    so now I have to question the other Schluter proudct, Ditra. I was going to install that on the plywood floor overtop of my floor heating system (Suntouch).

    any cautions on this before I risk creating any more mess?

    I was going to follow the process to put the the Suntouch down, thinset it with modified thinset (Mapei...don't recall kind I have). then ditra over that (not sure what thinset on that yet).

    then put porcelain tile over that.

  2. #17
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    I didn't notice if you said you washed the walls down first before installing the thinset. This is a crucial step, especially on cbu. Even if your thinset is mixed properly, it can make for a bad bond. CBU is REALLY thirsty, and can dry the thinset out way too fast...dried thinset doesn't bond well, cement needs moisture to hydrate and cure. Cement grows interlocking crystals when it has enough moisture to cure, and this is what makes the bond...not enough moisture, poor bond.

    All membranes must pass a bonding test and the number is 50psi, and tests show 75psi is typical on Kerdi and Ditra AFTER it has fully cured (industry standards are after 28-days for ANY mortar, this is not specific to Kerdi or Schluter). There's more than enough strength to start to lay tile on Ditra immediately after embedding it, and Kerdi as well. For maybe as long as a week, if you catch an edge, and try to peel it back, it will come off, usually tearing a bunch of the fleece off in the process, but it will come off. So, catching an edge with a vacuum, depending on how you caught it and how you moved it, how long it has been on the wall, and, obviously, the strength of the vacuum, you could damage the install further.

    In the example John showed of a poorly installed shower, it was obvious that they did not get good bond on the membrane. That is why it is critical to peel back the sheet to check occasionally to verify both the surface and the membrane are fully covered...you should not be able to see any of the membrane, and the wall should be covered with thinset, if it is done properly.

    Most of the time, when you embed the membrane, it ends up a bit sloppier on the surface because you run from the middle to the edge, and this pushes any extra thinset out of the seam. Your seams are pretty, but you may not have embedded things well, and may have excess thinset there. For certain, you don't want lumps, but neatness isn't particularly critical here...getting the membrane bonded well is, and that tends to be not what I see.

    Only way to be certain is to have someone look at it that knows and understands it well. It's hard to do from pictures.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  3. #18
    DIY Junior Member keithterry's Avatar
    Join Date
    Oct 2013
    Location
    Ohio
    Posts
    14

    Default

    Thanks for all the feedback, I do appreciate it.

    I did wash walls with sponge with water, about twice. but the juncture issue is at the foam tray, covered with kerdi band, covered with kerdi, right at where the kerdi meets kerdi band.

    I did embed by pushing the thinset in with a flat 6 to 8" blade (what would use to apply drywall compound). Schluter rep thought that was right. I got a lot of thinset out the side and worked out bubbles. it wasn't too messy on the edge, but there was some. it wasn't real wet though or mushy. I could pick it up and put it back in the bucket.

    of everything I've heard, the theory that the thinset wasn't wet enough and the heat kicking on dried it up too fast makes most sense. if I saw thinset mixed up correctly, I may be able to tell. I'll have to look for videos on that.

  4. #19
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    http://www.bostik-us.com/sites/defau.../Ditra-Set.pdf 5-6 quarts to a full bag. When mixed in the right proportions, it's about the consistency of mayonnaise. For embedding the fleece of Ditra or Kerdi, you'd probably want to go towards the top of that allowance. That works out to a little over 38oz water to 10# of dry thinset. Because Ditraset also qualifies as a medium bed mortar, if you needed that extra depth, you'd probably mix it towards the lower end of that allowance, IOW, closer to 5qt/bag verses 6 when embedding it in the fleece.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  5. #20
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default Kerdi Coll vs Ardex 8+9 vs Kerdi Fix to fix the wicking issue for a Kerdi Flood Test

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:18 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  6. #21
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    FWIW, as cement cures (hydrates), it creates interlocking crystals. If your thinset was too dry, two things happen, it cannot fully embed the fleece of the membrane and it may not have as much moisture as it needs. One reason why a dryset works between impervious materials is that it has what moisture it does have entrapped, allowing it to be incorporated into the cement's crystalline structure. Adding a bit after it was flood tested and leaked might allow it to further hydrate. The specs on bond strength do get better over time, and having the right amount of moisture maximizes that value.

    The main reason they developed modified thinsets was to retain the moisture to ensure a good hydration of the cement. Any other benefits were secondary. Since that only came about in the mid-1900's, and people have been tiling for centuries, a dryset, used between two impervious surfaces can achieve it's full strength without those additives, and since a modified is less stable until it has its modifiers dried, works better in these situations. The right material for the right situation.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  7. #22
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:19 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  8. #23
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:19 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  9. #24
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:19 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  10. #25

    Default

    Hi Keith,

    I can't tell from the pictures you've posted, but it's very possible there is no problem at all. If you are concerned, for example, about water wicking into the thinset you can see on the surface, don't be. I remember the first Kerdi shower I tested back in the day. I used white VersaBond thinset, and there was quite a bit of it smeared on the surface of the membrane (wiped over with a damp sponge and left to dry). When the water contacted it the thinset almost immediately changed from white to light gray. What we found, though, was that water didn't get very far into the seams, no more than a quarter- to a half-inch at most into the two-inch seams.

    You can't see the thinset inside the overlapped seams, and if they are tight I'm guessing the seams are fine. If the shower base contains water with no loss save for evaporation, your shower is fine.

    If you would like the opinions of tile setters with a lot of experience with Kerdi you are certainly welcome to return to the John Bridge Forum. It's a tile issue as much or more than a plumbing matter.

    "Jim," by the way, is a trained Schluter installer.
    John Bridge, Ceramic Tile Setter :-)

    http://johnbridge.com/vbulletin/index.php

  11. #26
    DIY Junior Member keithterry's Avatar
    Join Date
    Oct 2013
    Location
    Ohio
    Posts
    14

    Default

    Well I took the risk and tried the shop vac test and passed, I saw no instance where it pulls away.... whewww...

    best photo of what I see as leaching while running the water. it is darkness under in that area.
    Name:  2013-10-28 23.06.03.jpg
Views: 150
Size:  33.8 KB


    I spoke with the Schluter rep out here today (Art) who said the same as John oddly enough, may not be an issue, do a full water test over 24 hours. I have 1" water in there now. I re-measured the seam up the wall and was under the 2" required in overlap, on the lower side where I see the leach mark, it is 2.5 inches, so in spec there. makes me think I need to get some kerdi band and go over that joint to be in spec, or ardex it for safe keeping if I can get it...?

    I've found no source for Ardex around here (Ohio). looks like I could order it off the net. I like the concept of sealing those joints. but it sounds like it is not easy to mix right, I'll have to re-read Mr. Whipples posts on that. if I pass the water test, is it needed?

    Shower niche question: I found premade niches at Floor/Decor outlet called Ezniches. they are not presloped, but figure I can do that with thinset (modified). Their suggestion to install it was to use polyurethane adhesive (liquidnails) to adhere it to the wall. thoughts on if there is a better way. I could build my own with enough time and effort, but that's another thing to water proof. if the polyurethane is fully sealed around the sides I can see that being water proof. any experience that works?

    lastly when I put up tile, I need to put some holes in teh wall to scure a board to hold the first tiles right? fill those with poly or kerdi over them? I haven't asked schluter these questions, I will tomorrow.

  12. #27

    Default

    The Ardex certainly won't hurt, but I don't think it's needed. Schluter has tested the thinset seams over periods of time and under significant head pressure. They have found the maximum intrusion of water into the joints to be right at 3/8 in. There is typically no head pressure in a shower as the water goes directly down the drain. You have no problem.
    John Bridge, Ceramic Tile Setter :-)

    http://johnbridge.com/vbulletin/index.php

  13. #28
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:19 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  14. #29
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default Pass or Fail - Kerdi Water Test - All Pros Flood Test their showers

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:19 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

  15. #30
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default False read in a Kerdi Wicking Scenario

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:20 PM.


    jfrwhipple@gmail.com - www-no-curb.com - 604 506 6792

    Always get construction advice double checked by your local city hall. Flood Test Every Shower - Every Time.

Similar Threads

  1. install schluter flange to trap
    By jerome7 in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 3
    Last Post: 06-09-2013, 09:25 PM
  2. Schluter trim and my install
    By boardable in forum Shower & bathtub Forum & Blog
    Replies: 12
    Last Post: 11-29-2012, 06:28 PM
  3. Schluter's Line Drain - A closer look at the new linear shower drain from Schluter
    By johnfrwhipple in forum Shower & bathtub Forum & Blog
    Replies: 14
    Last Post: 07-15-2011, 07:47 AM
  4. Schluter-Kerdi shower install needed
    By cclearly in forum Shower & bathtub Forum & Blog
    Replies: 1
    Last Post: 10-31-2008, 01:06 PM
  5. can't install shower hot/cold knob! wall tile issue
    By suzie50 in forum Shower & bathtub Forum & Blog
    Replies: 1
    Last Post: 01-24-2007, 05:25 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •