Kerdi Shower Water Test

[John Bridge]

Put the Kerdi on the ceiling just for the fun of it. Doesn't hurt. No, you don't need it.

Yes, Kerdi works for stone tiles, too.

Started the wall tile today, but nothing fancy. That'll come Monday. I'll post more pictures then.

The Kerdi and thin set had completely dried out by the time I got there this morning. Even though water wicked up the exposed thin set, it won't pentrate more than a quarter-inch into the seams, and that would take a couple weeks to happen. With a minimum of two inches overlap at the seams, there's nothing to worry about. We had the floor flooded for 24 hours, and there was zero penetration in the seams.

You guys know that thin set is NOT waterproof. The idea is to press the seam tightly together. Don't leave a lot of surplus mud in the overlap. Do that, and I guarantee you you'll never have a leak.

[chase2000gt]

so... what do you do in the corners? You mention a pinhole, Im guessing that is literal?

[Indiana Floors]

What did you/ can you, install the kerdi over?

[jgleason]

The recommended substrate to put Kerdi over is regular drywall. It works, that's all there is to it. Check out the install videos on Schluter's site.

[cx]

Originally Posted by chase2000

so... what do you do in the corners? You mention a pinhole, Im guessing that is literal?

Well, a fella can see light through it, (insert first name here), which makes it literal enough, I suppose. But you can fold up a cut corner of the stuff and pour water in it like a dixie-cup and it won't go through the pin-hole.

And that's just dry, holding the fold together with your fingers. Hole's fulla magic, maybe? Dunno. But I know the water will stay in there longer than you wanna hold that cup together.

[John Bridge]

I recounted in Tile Your World my trip to the CTEF and Schluter training. I called the pinhole a "vortex," meaning I suspected water would run through there at an accelerated rate. That's the first time I witnessed the demonstration that CX mentions. Water just won't go through there.

(I still make sure I get a gob of pookie in the corner, though. Call it old school.

I assure you, there is nothing in those corners except the pinholes, and they held for 24 hours under head pressure. A shower, any shower, when in use encounters zero head pressure.

The new one-piece corners make the job go much faster, but they don't hold water any better than the "vortex" corners.

[John Bridge]

Here is a picture taken from The Kerdi Shower Book. You will see that not only is there a pinhole in the bottom of the cone, but there is nothing at all in the seam. Holding it just as I'm holding it in the picture, water will not go through the pinhole or the seam. It's magic, just as CX says.

[Hamilton]

You fellas are gonna make me stop muddin arent ya? Now do you gotta
let kerdi set for x-amount of time before you set on it, or can you go right
to it once its up?

[JTG]

Jack
I when I do glass backsplashes etc I will go right over a fresh set Kerdi. (it is a great glass membrane, especially large glass tile)
When I do a shower we almost always let it set overnight. If you are on the floor much it will move and lump the Kerdi fabric. Always save the big box the Kerdi kit comes in to put down on the floor.
JTG

[Hamilton]

From the closeup photo kerdi looks like composeal gold, which is what i use
for exterior underlayment .... only thinner.

[John Bridge]

Whether you set over it immediately depends on what time of day you get it up. If I finish a Kerdi installation in the morning and want to work the whole day I start tiling immediately. Sometimes I leave the floor membrane out and start tiling one course up. I can then install the floor membrane later.

On the other hand, I have found that if I really work the floor membrane to get all excess thin set out from under it that I can get on it immediately without causing any damage. Put cardboard over it, as Jerry mentions. Scraps of sheetrock also make a good covering. I have never used the foam floor, so I'm always working over deck mud which I think must abosorb moisture better than the foam, which is waterpoof or nearly so.

The beauty (one of the beauties) of the Kerdi shower is that you can adapt the process to suit your schedule.

Jack, I still have to mud a shower once in a while when specs call for it, but I fight it tooth and nail. Geez, I'm getting lazy in that regard.

[John Bridge]

Just a few progress pics.

[opiethetileman]

4th row over 12 th tile up the beige one yeah that one on the floor looks crooked now fix it boy you getting slow. Haahaaa nice lookin job John shame to cover up that orange with tile. how did you get them puppies to stick on the ceiling unsanded thinset??? why do you use reg tape and not blue?? the expense??? I wish I had that pan to do i just had to tile 9 bathroom floors in a bar with drains with 18x18's talk about going postal. oh yeah john few more of them showers and you will be retardment soon.

[GatorFan]

I feel like a DA for asking, but why the tape? I know there is a perfectly good reason or else it wouldn't be there. Shower looks great!!

[opiethetileman]

Albert cant mix thinset rite so John has to keeep it from saggin. I am sure John is a dead eye ball guy. I use to work with a guy just like John. The guy has his first level and trowel for the 40;s on his truck. Its just them old ducks you cant teach new tricks too. i sure its cuase the tile aint that square either.