Ceramic Tile Advice Forums - John Bridge Ceramic Tile

Welcome to John Bridge / Tile Your World, the friendliest DIY Forum on the Internet


Advertiser Directory
JohnBridge.com Home
Buy John Bridge's Books

Go Back   Ceramic Tile Advice Forums - John Bridge Ceramic Tile > Tile & Stone Forums > Tile Forum/Advice Board

Sponsors


Reply
Thread Tools Search this Thread
Unread 11-25-2020, 05:37 PM   #1
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Kerdi Board Question

I’ve tried to find the answer to this question, but haven’t found anything. Sorry if this has been asked before.

So I am using Kerdi Board and Kerdi Band to waterproof a bathtub surround and a shower surround. Shower has an acrylic base.

I installed the Kerdi Band to the bathtub surround one night. Took way longer than I thought it would, and towards the end the thin set wasn’t covering as well as to start off with. I was still getting full coverage (I was constantly pulling back and checking my strips).

I took a break and decided to start on the shower. I did the bottom of the shower at the tile flange. When I pulled back to check I had like 25% coverage. It was getting late in the night and I was getting frustrated so I pulled it off, scraped off the thinset I applied, wiped the area with a damp sponge and called it a night.

Now I’m questioning if it is OK for me to start from where I left off and apply new thinset to the little bit of dried thinset that was left, or did I create a problem and do I need to replace the Board along the bottom of my shower?
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Sponsored Links
Unread 11-25-2020, 05:55 PM   #2
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Picture attached
Attached Images
 
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 06:20 PM   #3
smifwal
Registered User
 
Join Date: Mar 2016
Location: Kansas City
Posts: 1,484
I don't see why not, you only have a "skim coat" on the board and no big build up, lumps or holidays correct? Wet it with a damp sponge and charge a head.

Also beer helps with minimizing the tried and frustrated pissed off throw your hands up moments
__________________
Shawn
smifwal is online now   Reply With Quote
Unread 11-25-2020, 07:37 PM   #4
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 91,897
Welcome, Jonathan.

The whole principal behind achieving a waterproof joint in the Kerdi fabric is to get the fleece on both layers of membrane fully wetted by the very thin layer of thinset mortar between them. Thinset mortar is not waterproof, so it's the very close contact of the fleece on each layer that seems to make the watertight seal.

Once you have applied thinset mortar to one side and allowed that mortar to cure and dry, you no longer have the ability to make that connection you have with the clean fleece and wet mortar. It's no longer the same joint.

Can you get by with what you've got? I dunno. Will your new overlapped seam be the same as the seam you'd get with two clean Kerdi surfaces and wet mortar? No, it won't. Will it be waterproof? Maybe.

The new materials coming on the market in the tile industry provide some good options for waterproofing methods. Many of them I really like. But they do come with some requirements for attention to detail that were not as prevalent in the more traditional shower construction methods and the user needs to be aware of some of the challenges.

My opinion; worth price charged.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Unread 11-25-2020, 08:43 PM   #5
smifwal
Registered User
 
Join Date: Mar 2016
Location: Kansas City
Posts: 1,484
well I feel dumb, I clearly wasn't thinking... Do you have any larger rolls of kerdi other than the banding? you could go up 2 inches above the highest part that is covered in thinset
__________________
Shawn
smifwal is online now   Reply With Quote
Unread 11-25-2020, 10:07 PM   #6
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 91,897
Nothing to feel dumb about, Shawn. You gave your opinion of the situation, I gave mine. I can't prove either of us is right or wrong.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!

Last edited by cx; 11-25-2020 at 10:16 PM. Reason: typo
cx is online now   Reply With Quote
Unread 11-25-2020, 10:08 PM   #7
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Thank you for the welcome! Been lurking for a while and finally had a question I hadn’t seen answered before.

That’s sort of what I was afraid of.

Kind of regret going Kerdi on these ones. The board is a dream to hang. The band is a pain in the butt, to be honest. Roll on membranes are so easy.

I do not have any larger rolls of Kerdi. I’m kicking myself for rushing things. I’d of course much rather have things done correctly than quickly. Luckily this Kerdi board stuff is dirt cheap... I do have a chunk of board left. Question is do I replace two big chunks or just take out the sections I ruined? I did such a good job minimizing seems, too. Darn it
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 10:08 PM   #8
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Maybe I’ll call Schluter tomorrow to see what they say. I’ll let you all know...
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 10:14 PM   #9
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 91,897
The liquid applied membranes appear to be so easy because you rarely see them being applied per the manufacturer's instructions. For walls I think they're OK, for shower receptors, not so much.

If you have some KerdiBoard left over, my recommendation would be to cut out and replace those sections covered in thinset mortar and cover the seams with KerdiBand. The KerdiBand installation is really quite simple if you've mixed your mortar correctly and used the proper notched trowel to apply it. Then I prefer to use drywall knives to apply the KerdiBand.

You were using Kerdi Fix to bond your band to the receptor's tiling flange? I can't tell from your photos.

[Edit] You got that last post in whilst I was typing. Calling the Mother Ship is always a good idea, but I doubt you'll find anyone there tomorrow. 800-472-4588

My opinion; worth price charged.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Unread 11-25-2020, 10:18 PM   #10
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Ahh I’ll call Schluter Canada since I live in Canadia.

I do have Kerdi Board leftover. I likely do not have enough Band. Trip #457 to the hardware store here I come...haven’t gone in 2 hours or so, so I’m due.
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 10:19 PM   #11
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Yes I did use a ton of Kerdi Fix, as per Schluters instructions. Seemed completely ridiculous as there was really only a maybe 1mm gap tops that needed waterproofing.
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 10:25 PM   #12
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 91,897
Don't understand that comment. The Kerdi Fix is only to bond the Kerdi to the tiling flange. You shouldn't be filling any gaps with it.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Unread 11-25-2020, 10:33 PM   #13
wetcoaster
Registered User
 
Join Date: Nov 2020
Posts: 12
Oh the Schluter instructions tell you to fill the entire tiling flange with Kerdi Fix, which seems like overkill to me. But those Germans undoubtedly know better than me so I just followed the instructions.
Attached Images
 
__________________
Jonathan
wetcoaster is offline   Reply With Quote
Unread 11-25-2020, 10:38 PM   #14
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 91,897
Yes, you would wanna cover the entire tiling flange with the Kerdi Fix and Kerdi for a good bond. If that also gets into the gap above, that's fine, but you needn't make a point of it.

Good actually to have a bit bigger gap above the flange and give the membrane a little bit of a wedgie into the gap for better movement accommodation.

My opinion; worth price charged.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Unread 11-25-2020, 10:46 PM   #15
jadnashua
Veteran DIYer- Schluterville Graduate

STAR Senior Contributor

 
Join Date: Jul 2004
Location: Nashua, NH
Posts: 14,205
You may have run into the limits of the thinset pot life...the chemical reaction stops for no man! One of the hassles of low experience...things take longer and it's not uncommon to mix more than you can use before things fire off.

One of the other things with working with Kerdi is how you mixed your thinset. The instructions may seem like you can take liberties, but you really need to follow them for best results. That includes the right ratio of powder and water, the right paddle, the right speed, and mixing it the specified time; waiting, then mixing it again.

To properly embed Kerdi, the thinset needs to be mixed using the maximum allowed so it is not thick, but just able to hold a notch. SEtting tile on it, you want it a little thicker, but thinset doesn't technically bond to Kerdi, it holds because it flows around the fleece and cures. Too thick, and it doesn't embed things well, and the bond is weak.
__________________
Jim DeBruycker
Not a pro, multiple Schluter Workshops (Schluterville and 2013 and 2014 at Schluter Headquarters), Mapei Training 2014, Laticrete Workshop 2014, Custom Building Products Workshop 2015, and Longtime Forum Participant.
jadnashua is offline   Reply With Quote
Reply

Stonetooling.com   Tile-Assn.com   National Gypsum Permabase


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Kerdi-Board/Tub Question RobinSue Tile Forum/Advice Board 7 09-19-2018 09:37 AM
Kerdi board question on alcove tub flange Leah F. Tile Forum/Advice Board 10 04-16-2016 03:27 PM
Kerdi Board Curb Question jbaskins16 Tile Forum/Advice Board 2 09-18-2011 07:50 PM
Kerdi question on Ledger board/punctures... Brian@BC contracting Tile Forum/Advice Board 13 03-27-2009 03:05 AM
Cost question between cement board and kerdi larry528 Tile Forum/Advice Board 4 09-09-2007 06:45 AM


All times are GMT -6. The time now is 10:34 AM.


Sponsors

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Copyright 2018 John Bridge & Associates, LLC