Ledger Board? [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


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05-17-2015, 06:41 AM
Tiling a shower and the preferred method seems to be to start with the second row and set it on a ledger board. When using a kerdi membrane its not really possible to install a ledger board. So what is the process in that situation? Do you set the first row and set the wall tile on the floor tile?

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05-17-2015, 07:39 AM
Ledger boards are used all the time in Kerdi showers. After removal, just squeeze in a health dose of Kerdifix or Sikaflex in the holes. Perfectly acceptable. :deal:

05-17-2015, 07:54 AM
That makes things easy. I was actually researching silkaflex when you replied. Home Depot has several different kinds of silkaflex. There is the White-Construction-Sealant-90618/202529347 at home depot. Forum won't let me link but here is a shortened link:


Just paste the above in your browser. Is the stuff I linked to the proper stuff?

05-17-2015, 08:04 AM
Dax, you can use a couple of screws to hold a ledger on and then either plug the holes with Kerdi Fix or a Kerdi patch.

I sometimes do it this way, so as to not compromise the membrane. Photo shows Kerdi board scraps, but could be done with ply or osb. I don't remember why I started up two courses on this shower, but musta had a reason.

I shoot a level line with a laser and line up my ledger and then use spring boards to hold in place, but then I always have this stuff laying around shop, so there's that. Spring boards are an old carpenters trick.

05-17-2015, 08:10 AM
Hi Peter,

Thank you so much for sharing your photo! Very clever! I'm going to borrow that trick!

I noticed in the photo there appears to be some patches in the Kerdi on the walls. Was that spots where it looked like the Kerdi might not have adhered or did you patch for some other reason?

05-17-2015, 08:18 AM
It's Kerdi board, Dax, and those are covering the attaching screws and washers. This just happened to be the one I took photos of, I've done same ledger setup with Kerdi membrane.

If you plan it right with sides holding back in place and spring boards bowing down in middle, the back can be sprung from curb and you can move around on your knees with care to save reaching over the whole mess to set back wall tile.

05-17-2015, 08:27 AM
Dax~Yep, that's the right stuff. After 3 or 4 posts, you can put in links. Anti-spam measure we have in place......

05-17-2015, 10:26 AM
Dax, if you use a ledge board and plan to patch the holes with Kerdi, be sure the holes are at least 2" below the top edge of the board so you can get a full 2" of overlap to patch the hole. If you plan to use Kerdifix or equivalent, it doesn't matter so much.

Peter, maybe you started two rows up to line up with the top of the bench? :)

Tool Guy - Kg
05-17-2015, 12:32 PM
I often cut a board slightly long and spring it between the walls and is held in place by friction alone. If I feel I need it, I'll attach a "leg" on either end to the face of the ledger with self-tapping short screws.

Or you can purchase a wall level support gizmos like these (http://www.raimondiusa.com/ta_wl_lvl.html) from Raimondi.


05-18-2015, 08:18 AM

Didn't you start on row 2 so that you could align the top row with the bench top? ;)

05-18-2015, 08:30 AM
Didn't you start on row 2 so that you could align the top row with the bench top?
Peter, maybe you started two rows up to line up with the top of the bench?

We have a consensus! I feel better now:yipee:

05-18-2015, 10:28 AM
For the spring boards, what wood/material/thickness works well? I'm sure I could figure something out but rather than experimenting I thought I'd just ask. I don't have anything thin enough to flex on hand and will have to pick something up.

Also, I've seen a couple of different youtube tiling videos today where the tile on the shower floor was laid after all of the wall tile was put up. I thought that you always want the wall tile to sit on top of the floor tile?

Thanks so much for all of the great help. You guys are the best!

05-18-2015, 06:02 PM
Dax, I usually have some narrow scraps of 1/4" or 3/8" ply that I rip to 1 1/2 or 2" strips. Probably not much over that or it'll be hard to flex.

The floor thing is a matter of taste and appearance. The waterproofing doesn't care.

I like the wall tile to land on the floor as you're indicating, so sequence is walls, floor, bottom course to fit. Some here wait to set floor and bottom course till they've grouted walls, so they don't have to worry about dropping stuff on tiled surface. I tile all then mask or cardboard or whatever on floor to catch the grout blobs...and there will be errant grout blobs.

Houston Remodeler
05-18-2015, 06:36 PM
I'm going to steal borrow use the spring board idea !


05-18-2015, 07:29 PM
Thanks Peter. I'll pick up some 1/4" and rip to size.

When you set 8 x 8 do you mud just the tile or do you do the wall and the tile both?

05-18-2015, 08:25 PM
Hey guys...see i was always taught to do it the opposite way. When i start my walls i set my shower floor first. i take a laser level and put it up where the top of my first row is and set my whole first row first. once thats nice and level you can roll up with everything. never used the board method.

05-18-2015, 08:38 PM
8" tiles on the wall usually don't require mudding the tile backs. You can just comb the walls and go. An exception would be if you had tile with deep cavities on the back, so much that you didn't have good contact. That's the key, having good contact between thinset and back of tile.

I would probably use 1/4" trowel and check the first couple of tile after setting. If you find you aren't getting good contact, then use the flat side of the trowel to skim the back of the tile.

Alternately, you could mud the back of each tile, combing the thinset with the notched side of the trowel. Of course, then you would need to skim the wall with the flat side of the trowel. It's really just a matter of preference.

05-19-2015, 12:36 PM
Thanks guys. I was seeing youtube videos where "pro" tilers were combing only the backs of the tiles and not putting anything on the wall. Certainly makes tiling easier but I was wary that was correct.

I have a mud pan with a pre-pan, liner and then the final pan ready to accept tile. I set the top of my drain so that it will be just ever so slightly below the final height of my floor tile. I want to do a flood test before going any further. Just to verify I didn't put a hole in the liner or have other issues. So my drain is above the level of the masonry which means when I'm done with the flood test the majority of the water can drain out but what's left would have to go through the masonry pan to the liner and then find its way to the weep holes in the drain. Unless I mop up what's left.

So apparently its not a concern that you would have all this water infiltrating the masonry pan down to the liner?

05-19-2015, 01:26 PM
That is what the deck mud and weep holes are for, Dax. :)

05-19-2015, 01:37 PM
Dax, the proper time to do a flood test is before you place the final mud bed. If you try to do a flood test now, you're gonna need to allow time for the water to saturate the mud bed before you'll be able to tell if any of it is leaking out of the pan. Not always a very straight forward matter.

How old is your mud bed at this point?

If you wanna notch the back of your tiles instead of the walls you'll still wanna skim coat the wall before setting the tile.

My opinion; worth price charged.

Houston Remodeler
05-19-2015, 01:46 PM
Particularly with Kerdi and Kerdi board, I have found it nearly a requirement to burn in a layer of thinset into the fleece to get it to grab the best. Sometimes the thinset can easily 'roll' off the kerdi fleece.

05-19-2015, 01:52 PM
The only possible way the pan could leak is if I accidentally put a hole in the liner while working on the shower after the mud pan was complete. No way could it leak after I had just installed the pan unless the liner had a hole in it brand new. I put silicone between the liner and the drain where it clamps together. I put tar paper between the walls and the liner to protect the liner. I would be absolutely shocked if it leaked because there is nothing anyone could do beyond what I did to do it right.

Even so...before installing a lot of expensive tile I'm going to test it. I'm not tiling until Saturday so I can fill it and let it sit for a few days. But then I will have to let it dry for a few days too, I imagine.

05-19-2015, 01:54 PM
How old is your mud bed at this point?

05-19-2015, 02:08 PM
It was done 3 - 4 weeks ago.

05-19-2015, 02:15 PM
Should be safe enough to saturate.

05-19-2015, 07:21 PM
The other thing about flood testing is the bottom edge of my durock would be sitting in water. Right now there is a 1" gap between the top of the pan and the bottom of the durock. That was by design so that the durock doesn't wick up water. The wall tile would cover the gap. That's for normal use. For the flood test the durock would be sitting in water. Is that a problem?

05-19-2015, 07:28 PM
Once it's thoroughly saturated, you should have a steady water level. It may take overnight for that to happen, maybe longer.

05-19-2015, 09:34 PM
Your Durock will wick some water during your flood test. It will do no permanent damage to the product.

My opinion; worth price charged.

05-20-2015, 11:14 AM
Have I correctly interpreted that you have built a traditional liner with Kerdi over Durock walls? I'm trying to picture the interface between the two methods.

05-20-2015, 01:38 PM

Yes. The liner extends up the stud wall about 6 inches. The durock goes on the wall (covering the liner) and stops 1 inch from the top of the mud pan. You don't nail or screw the durock to the studs any lower than a couple inches above the top of the curb because you don't want to puncture the liner too low and risk a leak. The 1 inch gap between the bottom of the durock and the top of the mud pan eliminates the durock from sitting in water while the shower is in use and prevents water from wicking up the durock. That gap will get covered by the wall tile.

The kerdi membrane covers the durock to prevent water migrating through the durock. Since the durock is inside of the pan, any water will travel down the kerdi membrane into the pan. Same concept as a traditional pan and using redgard on the durock as the waterproofing but the kerdi membrane is better (IMHO) than a painted on waterproofing.

05-20-2015, 02:29 PM
The liner extends up the stud wall about 6 inches.Before you get any further into this, Dax, the minimum requirement for that liner is six inches up the wall or three inches above your curb, whichever is higher.

05-20-2015, 03:12 PM

I'm good

Tiger Mountain Tile Inc
05-21-2015, 07:39 PM
Dax, I just reread this thread from the beginning and I'm confused on how you are building your shower. Correct whatever is wrong, but it looks like a Kerdi shower over cement board with a traditional-type liner pan? But for some reason the cbu is 1" higher than the pan?

05-21-2015, 08:10 PM
but it looks like a Kerdi shower over cement board with a traditional-type liner pan? But for some reason the cbu is 1" higher than the pan?


Correct. Maybe an illustration would help. Go to this video:


and skip ahead to minute 42 which is almost to the end of the video and start watching from there.

The idea is you want your CBU to stay dry. If the end of the CBU is sitting in water it can soak up some water. I don't think cement board would soak up much...other materials might be worse for that sort of thing. But it makes sense to leave a little gap to control the water and prevent it migrating anywhere.

05-21-2015, 08:35 PM
David, don't watch any more videos from that guy. His theory is correct, but his execution is not good. His problem, which you will not have, is that he is using Densshield, which has a gypsum core. I didn't have to watch the rest of his video to see that his shower is going to be a mess in a very short time.

The wallboard when installed in conjunction with a PVC liner does need to be held up off the pan 1/2" or so. Yours will be fine since you are using cement board. Doesn't matter if it gets wet, since water won't damage it. What he's using will get water damaged, regardless of the waterproof face of it. The edges of Densshield aren't waterproof.

05-21-2015, 09:17 PM
Hi Kevin,

I've pretty much found when you watch these videos you have to sort through the good points and the questionable points and use some common sense. This same fellow had another video where he nailed backer board to the inside face of the curb (nailing through the liner) where he had nails below the level of the curb. Not good. But then he also had a lot of outstanding advice on how to, for example, level your studs using a power planer, sistering studs, etc. Lots of good information and I found him to be very knowledgeable. He is a big fan of denshield.

I know durock is a better product for showers. Some people don't like it because its more difficult to work with. But I had no problems cutting it with a utility knife and snapping it like sheetrock. Then using a grater to clean up the edges. I found it totally easy to work with.

In my mind it all comes down to controlling the water. Thinking about capillary action, etc.

05-21-2015, 09:28 PM
Let me clarify my earlier post, after re-watching his video, and listening to his explanation in particular. He did in fact say to keep the board out of the mud, which in the case of Densshield would be the proper way to install it, as long as he seals that gap with a flexible sealant. I still wouldn't use it, just out of personal preference, but that's a different argument.

I also saw the next video he posted with the cement board on the curb and about 20 nails and screws. He also had a ton of screws in the Densshield, and while he might have sealed them, I doubt that he did.

Back to your regularly scheduled project. :)

05-21-2015, 09:47 PM
Let me clarify my earlier post, after re-watching his video, and listening to his explanation in particular. He did in fact say to keep the board out of the mud, which in the case of Densshield would be the proper way to install it, as long as he seals that gap with a flexible sealant. I still wouldn't use it, just out of personal preference, but that's a different argument.

I also saw the next video he posted with the cement board on the curb and about 20 nails and screws. He also had a ton of screws in the Densshield, and while he might have sealed them, I doubt that he did.

He actually does seal everything very thoroughly. He uses a combination of some kind of material with a painted on membrane.

I see that Schluter says you can use sheetrock for a shower with their membrane and while it might work if everything is done perfectly it leaves no room at all for the slightest glitch.

Seems like there are all kinds of ways things can be done. Whether they should is a whole other story!

Tiger Mountain Tile Inc
05-22-2015, 10:05 AM
Hi David and thanks for the link to the video. At first I was starting from the 1:42 mark and couldn't figure out what was going on then I reread your post and realized it was the 42 minute mark. :dunce:

I don't know how he ended up finishing that but I'm assuming that the Denshield didn't get embedded into the final pan and stayed on top of the mud. This would be the proper way to install that because of it's gypsum core. It's supposed to be about 1/4inch or so above the mud and then caulked around the bottom so water doesn't wick. This is according to TCNA method B-420. I put the method in so that people know I'm not just making up my own standards but that there is a written standard for installing that material in that application.

Cement board should be embedded into the pan. I prefer the wall board being embedded into the mud so that's one of the reasons I use cement board on the walls as opposed to other products.

Granted, anybody can do it anyway they want. But in the case of Dax and this thread, I just want to make sure he knows what the proper way is. If he wants to veer off from there that's his business. :)

05-22-2015, 02:05 PM
What is the benefit of embedding the durock into the mud pan? I have a suspicion I know why but wanted to hear what you thought about it before I say anything. :)

05-22-2015, 02:34 PM
Since you're not supposed to have any fasteners for at least 3" above the level of the curb, the bottom few inches of the wall board can be left flapping in the breeze. But if you use a true cement board, it can be buried in the mud bed, which will hold it against the wall.

05-22-2015, 10:45 PM
Hi Kevin,

That's exactly what I thought you were getting at.

I did read that the 3" above the curb requirement for fasteners isn't required if you use a membrane like Kerdi. I was skeptical of that. Obviously if the membrane covers the screws it can't leak. But the screws also go through the liner. So to be safe I think its wise not to put any screws lower than a couple of inches above the top of the curb.

05-22-2015, 10:53 PM
I did read that the 3" above the curb requirement for fasteners isn't required if you use a membrane like KerdiDavid, that would be true only if you were using the Kerdi or similar direct bonded waterproofing membrane for your entire shower waterproofing system, including the pan or receptor.

If you have a traditional mud/liner/mud shower pan, you may not use mechanical fasteners within two inches of the curb top regardless the wall water containment method.

My opinion worth price charged.

Tiger Mountain Tile Inc
05-23-2015, 12:59 AM
Kevin answered it. With the liner folds it makes the bottom of the wall board flappy and usually means regularly repairing the bottom caulk joint around the pan.

05-23-2015, 01:03 PM
Hmmmmm, well, if that was the only thing I could have done better on my first shower then I can't complain too much.

I was thinking of running the floor tile under the ends of the durock which would leave about a 1/2" gap which I'm going to fill with adhesive silicone -- which should help bond the ends of the durock in place. The wall tiles will cover the gap and then where they meet the floor tile they will also be siliconed too.

You have to push pretty hard on the bottom of the durock to get any movement as it is. With the above hopefully there won't be any movement.

I guess time will tell. At least if anything ever needs fixing I can do it.

05-27-2015, 06:00 AM
Thanks for the awesome suggestion on using the bender boards to hold the ledger boards in place. That was a slick trick.

I started tiling yesterday and it worked awesome. Setting the ledgers with a rotary laser also helped tremendously. The ledgers were more perfect than I could have done with a float level.

Do you generally leave the ledgers in place until ready to do the bottom row or do you remove them after the first few rows of tile have been set and allowed to dry a few days? I can leave the ledgers but would have to step over the bender boards while working.

05-27-2015, 06:56 AM
Dax, I take 'em out the next day. Gets them out of the way and also I can check for thinset goobers that may have squooshed behind.

05-27-2015, 08:41 AM
That makes sense. I couldn't see any reason to leave them in place. I'm not completely done with the first course all the way around the room yet so they will stay in place for a while yet but I'll remove them when it makes sense to do it.

05-27-2015, 08:03 PM
Hi All,

I'm installing 8 x 8 tumbled travertine tile in my shower.

I've been watching the vertical grout lines to keep them in-line and plumb but I'm having problems with some tiles being wider than others.

Since the travertine has both square and rounded corners I've found I can trim a little off the wide tile and it still looks good and isn't noticeable.

But I keep thinking if I trim some off a tile I may have to trim some off the tile that sits directly on top of that one, and so on....

I tried narrowing up some of the grout lines between tiles leading up to the wider tile but I couldn't get enough by doing that. Ended up having to trim the wide tiles.

What is the recommended way of dealing with tiles like that? Is it common to trim them to keep the grout lines running plumb?

Any tricks to cleaning out thinset that gets in some of the holes on the face of travertine? I've been using a wet rag and a tiny screwdriver to dig it out best I can.

05-27-2015, 09:47 PM
If your tiles vary that much in size, you need to adjust the size of the grout joint to accommodate that. It may be too late for that now if you're well into the installation. The rule of thumb is that the grout joints should be three times the largest variation in size. So if your tiles vary 1/16" from largest to smallest, your grout joints should be 3/16".

Even then, sometimes it can be difficult to keep the joints somewhat consistent, and you'll find yourself adjust tile this way or that way to keep them as close to consistent as is possible.

If you're too far in to make that adjustment, you may be stuck with trimming them as you've been doing just to get by.

Tiger Mountain Tile Inc
05-27-2015, 09:50 PM
How much do they vary in size and how big of a grout joint are you going for?

Typically, I won't trim the tiles unless it's just one or two outliers (and then I probably just wouldn't use them). If the tile are what I'm thinking of then trimming will leave too sharp of an edge and would stand out from the others.

So usually I just try to split the differences and try not to get too many big/little ones in the same area. A blending grout will smooth things out for the final product.

But it's frustrating for sure.

edit: Are you finding that the tile sizes are changing all of a sudden? For instance from box to box? or are all the sizes in all of the boxes?

05-28-2015, 09:58 PM
I'm doing 1/8" grout joints. But with tumbled travertine when you grout the joints they typically look like they are about a 1/4" wide due to the rounded edges of the tiles. So that should work in my favor considering I'm having to vary the grout joints some to deal with the tile size issues.

I'm seeing a difference of up to 1/4" in the size of tile coming out of the same box. Its been working well to trim the wide tiles. Honestly, you can't tell which tiles have been trimmed. It just means more work for me because everything has to be checked and double-checked and adjustments made as I go along.

I've had to pull tiles off and most are almost impossible to get off and require prying with a drywall knife to get them to pop loose. I'm talking after I just set them 2 minutes before. I'm getting really good thinset coverage on the tiles. However, I've found a couple tiles where that wasn't the case and had poor coverage. So I've started back buttering the tiles with thinset before i set them. There is no thickness to the thinset when I back butter, its mostly keying it into the back of the tile and scraping off excess. I'm also making sure every tile is slid side to side and pressed in hard when I set them. Hoping that will give me more consistent results.

05-28-2015, 10:06 PM
That's not uncommon with tumbled stone. It helps if after doing a few square feet you back away from your work several feet and take a wider view of it. You'll be more able to see if everything is straight, and what needs to be adjusted.

05-31-2015, 06:54 AM
It was ugly. Turns out in was only 1 box that had the larger size and as bad luck would have it out of about 12 boxes I had to pull that one as the 2nd box. If it had been the 4th or 5th box I'd have questioned it. But I was setting the base courses and didn't catch that these were off. So now I have a few grout lines that are 2 - 3 times wider than others. Really pisses me off. I'm a perfectionist.

But there was nothing I could do after the fact. I couldn't even remove them and replace them as pulling them off destroys the wall.

When you grout travertine, because of the rounded edges of the tile, the 1/8" joints will look more like 1/4" or larger. So on those larger joints I'll take a toothbrush and take any extra width off and hopefully can fudge it so they look the same as the others.

I won't ever buy tile from this place again.

05-31-2015, 04:47 PM
Dax, it's not necessarily the retailer that is the problem. Even with ceramic tile, it helps to pull from several boxes at a time while installing. That way you don't have a long run of a different size/shade of tile, but rather an occasional one or two thrown in the mix. It's even more important to do so when dealing with natural stone which can vary greatly even within the same box.

05-31-2015, 05:22 PM
You need to be aware that many of the Big Box Stores are good, inthat they take refunds. At the same time, those "refunds," which might be over or underdsized tiles, oftentime get put into the "mix."

SO.......Check the dye lots carefully. It IS important.

06-02-2015, 10:42 PM
Thanks for the advice guys. I bought from "The Tile Shop" because they supposedly have better tile than Home Depot, Lowes, etc. I did notice its thicker tile. Also, "The Tile Shop" sells to pro tile setters, too.

It was just bad luck on my part. I have learned a lot on this project. I'm now mixing up tiles from different boxes and if I see a tile that doesn't fit correctly I just don't use it.