(206) 949-5683, Top Rated Plumber, Seattle
Page 1 of 3 123 LastLast
Results 1 to 15 of 42

Thread: Kerdi membrane install question.

  1. #1

    Default Kerdi membrane install question.

    I am building a walk in shower. the Sheetrock is up, time to start putting up the Kerdi.

    In demo video, they band all corners and lay sheets cut to each wall. Is there any reason I can't use single sheets to go around corners? I understand placing each sheet will be a bit more work, but, it would seem to me that fewer seams is better and also saves a little material. I was wondering if maybe it had to do with the thin set setting up very quickly, allowing little time to fuss with the kerdi.

    Or maybe Schluter likes selling Kerdi Band!

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

    Default

    It's much easier to use smaller sheets than to try to go around a corner. While Kerdi-Band is thinner and makes for a smaller buildup, you can use a band of the Kerdi material...it would depend somewhat on the tile you used whether that would be an issue. The last thing you want is to have the thinset skinning over before you get the last but up. Depending on the wall width, I've also not cut it, run the edge of the sheet around the corner instead of using the band material.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  3. #3
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default Install Answers for Kerdi Membrane - TCNA and TTMAC do NOT allow drywall in a shower

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:06 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.

  4. #4

    Default

    john, that was my thought as well, but the kerdi dealer says sheetrock is fine. i think it might have to do with the cement board sucking the moisture out of the thinset too quickly.

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

    Default Should drywall be used under Kerdi Membrane in a shower build? - Answer: No

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:06 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. #6
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    If you install Kerdi properly, the drywall stays as dry as it does in any room. A failure of your plumbing, while always possible, could damage it. But, a failure of your plumbing in any area of the house is problematic. Just do it right, and it should outlast the house.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

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

    Default Installing Waterproofing over Sheetrock or Drywall

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:06 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. #8
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    To be fair, almost none of the 'showers' being shown in the demos are real...they're mockup walls and floors, intended to show the application of the membrane, not the structure of the house.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

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

    Default What is the best drywall to use under Kerdi? - None - use a cement board

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:07 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. #10
    ACO Shower Drain Sales johnfrwhipple's Avatar
    Join Date
    Jul 2009
    Location
    North Vancouver, BC
    Posts
    2,993
    Blog Entries
    5

    Default What product is easier to apply over drywall? Kerdi or Ardex 8+9

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:07 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.

  11. #11
    DIY Senior Member DougB's Avatar
    Join Date
    Jun 2010
    Location
    Minneapolis - Land of 10,000 taxes
    Posts
    137

    Default

    John,

    I'm remodeling a bathroom, with an drop-in tub/shower in an alcove. I'm using cement board. Is there any advantage of using the Ardex product instead of Red Guard or Hydroban?

    For the rest of the bathroom, I was planning to use regular drywall, and tile over that. Is tiling over drywall OK? Should I prime the drywall first? What do you do?
    Last edited by DougB; 03-13-2013 at 09:39 AM.

  12. #12
    DIY Junior Member Amish Electrician's Avatar
    Join Date
    Oct 2011
    Location
    Arkansas
    Posts
    17

    Default

    Pete, I don't mean to 'pile on,' but .... NO GYPSUM in the shower! Not even the green or blue stuff!

    Yea, I know, various vendors make various claims. Read the fine print. There's a lot of 'maybes' in there. Murphy's Law will ensure that something goes wrong.

    I'm not a plumber; I do electric work. Several of my customers are property-management firms, so I get to see plenty of remodel work. I have yet to see a any gypsum product, any tile job, survive.

    So, when I do my bath, it will be cement board 100%, even on the ceiling. If nothing else, the cement board won't dent when you hit it with a mop handle. No paper or glue to feed mold, either. Skim coat it with real plaster, and it's as waterproof as steel plate.

    FWIW, my walls are getting covered with FRP (fiberglass reinforced plastic) sheeting. Absolutely waterproof, with very few seams - and none of the seams are horizontal. It's that pebbly stuff you see in commercial kitchens and public restrooms.

    Maybe I'm over-doing it, but the difference in materials cost is not that much. It amazes me that folks will spend a fortune on getting just the 'right tile,' yet compromise on the basic structure.

  13. #13
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,434

    Default

    Kerdi is a waterproof membrane. When it is installed properly, once you protect it with tile, no moisture penetrates it. John is a belt and suspender kind of person. Being in a business where you never want callbacks, it has some merit if people are willing to pay for it. Schluter has paid for an independent testing of Kerdi membrane installed over drywall and it passes all industry specifications for moisture protections IF IT IS INSTALLED PROPERLY. In my 60+ years, I've never had a belt or suspender fail, and have never worn both. You either believe the manufacturer and the testing, or you don't. They do not force you to use drywall, they also list other acceptable materials, which includes cbu. You use what you feel comfortable with and local regulations require. There are thousands and thousands of Kerdi showers in use today applied over drywall that are as dry as the day they were built. If you have a leak, it's either because of poor workmanship or an accidental puncture that occurred after testing and before tile. A leak would require fixing whether it was cbu behind it or drywall whether it was through the membrane or from a plumbing leak behind it. If you don't believe a single layer waterproofer is sufficient, then you'd want cbu on your walls and especially next to your windows in all the rooms of your house, or make the walls poured concrete. A house exposed to rain driver gale and hurricane force winds is a much more hostile environment than a shower. I trust my shingles and paint on the outside of the house to protect the interior walls as I do Kerdi to protect my shower. Feel free to augment it if it makes you feel better. I've got the certification test document somewhere, but you can find a copy on-line if you look. Since the test is only valid for a few years, it gets repeated, and has always passed. Most local inspectors will allow installation to the manufacturer's instructions with that certification. Some won't, and then you do what you have to should you want to use that material. There are lots of choices, pick one you're comfortable with, but installed properly per the manufacturer's instructions, they all work. Some give you more margin for error than others, but if you trust your workmanship and workplace environment to not compromise it, that's somewhat irrelevant. FWIW, in the USA (don't know what the duty is to Canada), you can pick up Kerdi membrane for around $1.75/sq ft fairly easily, including on Amazon. Many places offer free ground shipping. Also, if you believe the websites selling it, list price is in the order of $1.91/sqft. Canada can have some high tariffs on things, so your pricing could vary considerably as well as shipping.
    Last edited by jadnashua; 03-13-2013 at 10:04 PM. Reason: added Kerdi pricing in USA
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

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

    Default Kerdi Cost $3.00 per square foot @ Home Depot in Vancouver

    Post(s) deleted by John Whipple
    Last edited by johnfrwhipple; 03-15-2014 at 03:07 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. #15
    DIY Junior Member Amish Electrician's Avatar
    Join Date
    Oct 2011
    Location
    Arkansas
    Posts
    17

    Default

    OK, Jad, I won't debate your religion with you.

    "IF" is the biggest word in the language. Heck, I'd win the lotto IF I pick the right numbers. IF the Queen had balls, she'd be King.

    BTDT.

    So go ahead, get by with the minimum possible. I'm confident you also wear Wal-Mart $8 sneakers and drive a Yugo ... after all, they meet all the same regulations as the expensive name brands, so they must be just as good.

    While you're fumbling through all that documentation ... I seem to recall seeing somewhere that there were model codes that banned drywall and greenboard from 'wet' areas, like showers- no matter what was over them. You might want to be sure ... and get the permit and inspection as well.

    Everything I need to fix in my house is the direct result of someone being 'smarter' than the rule book.

Similar Threads

  1. Kerdi Membrane
    By DanMcD in forum Shower & bathtub Forum & Blog
    Replies: 8
    Last Post: 02-09-2014, 11:34 AM
  2. Kerdi Membrane VS Mapei Aqua Defense
    By Footman_75 in forum Shower & bathtub Forum & Blog
    Replies: 4
    Last Post: 02-03-2013, 09:54 AM
  3. Schluter Kerdi Membrane Source?
    By inertiacoupling in forum Shower & bathtub Forum & Blog
    Replies: 8
    Last Post: 03-30-2012, 06:07 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. Kerdi membrane question
    By khayes in forum Shower & bathtub Forum & Blog
    Replies: 6
    Last Post: 03-28-2007, 01:30 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
  •