Your integrity is why you are popular and respected.

Man, idk many contractors that will invest 3 days and that much $ to test the thing they install every day. Super helpful!

I will say, your tenacity to try to learn through experimentation as well as welcoming input from an open source is very admirable and puts you well ahead of the game, imo. I have no doubt that you will indeed be able to guarantee some future client a 100% waterproof shower. Excellent job, dedication to your craft, and great video as well!

As a tile guy of 20+ years myself, I'm proud that you represent the better of my industry. Kudos!

Best tile channel out there , you and home renovision ! Keep it coming

Great video! It was a lot of work on your part and I appreciate it.

Thanks for the level-headed response. To me, this great performance. Like you said, showers don't have standing water in them for 7 days. This one did and only had minor wetting (capillary action through the thin set and seams is my guess). It's just not an issue to me.

Pro contractor 33 years now, have use Schluter porducts in limited setup,was always very impressed. I have been very interested in using Kerdi for shower pans, But after watching this, I will stick to Vinyl liners. Your install is your reputation, stay with proven products. Kedri will still have place for walls etc, but not on a shower pan on my jobs. Thanks for the video

Great video love your posts. Schluter did a 7 day test of a 50ft deep pool and had 1.5" penetration of the 2" overlapped seams. "The wetter the better when applying the membrane." Each one of the fails had air pockets in the middle of the wet spot. These gaps pool liquid and saturate the mortar around, under, and inbetween everything.

You did a good job on the installation. Not to mention the movement or cracking that will occur in a standard installation with people walking over the surface. I always thought the spreadable membrane that you paint over concrete board looked more promising. But I am not going to tempt my luck by tiling floors. Its a shower pan for me.

Great video. I just did a Kerdi shower last week, and I was here partly to make sure I hadn’t done something wrong! Haha. Great channel - much love from your trades brothers & sisters in Canada 🇨🇦

Very instructive , you are a good teacher, THANKS FOR THE INFO., just learning, growing and taking in as much as I can, your not afraid to show fault in your work.

Awesome channel and great product test. I haven't used Kerdi but to me this fails for a tub but still passes for a shower stall. Keep up the great work

Excellent. I've been using Schluter for maybe four years now and I've decided to back it with Red Guard at the joints as a measure of insurance against fail. You just cannot go wrong with either product, altho Schluter is pricey. Red Guard alone is probably enough, but I don't want call backs. And, I'm a bit OCD. ;) Really good video, man. Thank you for taking the time to share your experience.

Really appreciate the delivery of your messages and the knowledge you share. Your genuine honorable mindset is awesome!

Thanks Isaac for taking your time on that video. Would be fun to see the same test with a liquid type membrane. All the best !

I always use 1/2" hardibacker, unmodified thinset, kerdi, then corners, then Kerri band, then regard EVERYTHING with 2 coats on walls, 3 coats on base upto 1'. No problems. I never use drywall as a substrate. I appreciate your efforts to make us better.

Very good test and about as thorough as you're going to get. Some people need to remember that the point is to replicate the best conditions out in the field, not some hypothetical lab setting. This is a good 'stress test' and another great video idea would be to have 3 or 4 small models: one with kerdi, one with redguard/aquadefence, one with both redquard and kerdi together and one of something else. Leave them for a week or two and compare all of them together.

Thank you for all your vids, it's very helpful to watch experienced guys in the field. I usually learn something even if its what not to do. Please keep posting.

I think you did the job way better than most would do in the field. Thanks

This was very worthwhile for all of us in the trade. Thanks. If I had to guess I would say a small section of that K band may have been compromised by the drywall knife. I use a heavier metal trowel, in conjunction with Schluter branded trowels. However my favourite trick is to smooth kerdi and jam corners using a poly rafter square. No sharp edges, you can be quite vigourous and forceful with it.

7 days under water and that's all that leaked for whatever reason... I'm sold. Simple but great test. Thank you.

The membrane held up great. You guys are good like your videos. I appreciate the no triple up on taping neatness and workmanship. The joint tape being the weakness I would find a way to tuck the corners and eliminate that leaking on another test. Considering doing a curbless shower on 3rd floor with an over lap layer from the wall down to the floor of shower as close to the drain as possible. Thinset over this double layer with inside corners embedded before a couple coats of aqua defense in corners and say a prayer before I tile it

Your videos saved me from making a costly mistake, thank-you!

Not just the actual work but the video recording and editing takes time too. A lot of effort here. thanks!!!

Cool test. I do think there essentially two reasonable ways to install Kerdi membrane. 1: Try and layer it like a roof with the top layers covering the bottom. I've found this is somewhat hard to do really well and leads to corners that aren't the flattest. 2: Install the corners and edges first then lay down the larger sheets. This creates much flatter corners and edges to attach the tile too.

Man i really appreciate these videos, they’ve helped tremendously throughout my projects.🤝

How satisfying is to see TCNA certified tile setters at work. Hats off to you guys

I’m a General Contractor.. 35 years in the trades , 15 self employed and have probably..I don’t know.. 100 full-set showers (built pan) and maybe a dozen fiberglass or vikril (Kohler’s propriety material ) out there.. I’m a self taught tile pro and the evolution has been from vinyl to hot mop to just recently Kurdi products. The speed and cost savings of the Schluter products are impressive. I’ve found that it’s all about the mud and precision of the install. Big fan of the pre-sloped foam pans , kurdi nooks and Prolite thinset has given me the best results. My paranoia has me knife in some sanded urethane caulk (Vulkem116)on tough odd angle inside corners where I can’t use Kurdi corners. Especially if the stone is particularly porous and we all know that unless you call and tell a client or offer to follow up resealing the grout and stone at least every 2 years? It won’t happen and you’ll get weep down to the felt. I’ve been using miracle products and they treat me well. I’ve had one failure.. Inside neo-angle corner right under a rain head that was getting 4 + showers a day. Young couple working and going to the gym and using the shower constantly. It was over an unfinished garage and hubby had a weight bench .. laying down looking up.. Spotted a small wet spot on the subfloor inside the shower wall shoe.. That shit won’t fly so I meticulously cut out the the 2x2 porcelain floor tile and popped a 12x24 and like a surgeon.. dissected the corner. What I find? Small cut in the corner through the membrane. I smoothed the band with a 6 in taping knife (I keep my stuff razor sharp) and nicked it. That’s when the Vulkem started happening. Unless you get perfect thinset coverage, no bubbles and 2-3 inch laps AND DONT CUT THE FELT LIKE A DUMBASS ..A pass with a 1 in knife over the seam with caulk just provides a little extra measure of insurance. No issues with bond over the urethane as long as you don’t over do it. Maybe I set up a 7 day immersion with my paranoid urethane caulk and see if she weeps?

I never did trust using thinset to bond Kerdi membrane. Bonding a waterproof product with a non waterproof mortar was not adding up. To me using Kerdi-Fix to bond corners and band made more sense and I did do a 2 week water test. No water seepage. Great video !

Thank you for your videos and testing. Great contribution!

You're very respected amongst your peers and I'm sure many of us DIY'ers as well for dedicating your time and energy to keep us well informed of new products and methods used in your trade and industry. Thank you

Lesson here is don’t use a sharp corner tool to do corners, because you’ll never know if you’ve compromised the band by puncturing it. There’s many tools with burred edges that will work great and won’t snag the material

I watch your videos regularly to improve overall comprehension of install and tile systems. Thank you sharing your skill and knowledge in what I believe is a very efficient way. I think you are great and much respect !! Cheers

Very helpful, I truly appreciate you and the time you invested to make that educational video. Thank you and god bless you brother😊

Great video and insight thank you. Kerdi would NEVER do a test like this.All and all this is still a "great" product regardless. No one will EVER leave water at that level for 7 days (at least I hope not). This is why I use pressure treated wood when framing in a shower/steam shower. Just incase .Absolutelt great video Thanks much again

I agree with you Tony. I have never considered the adhesive as a water proofing. I also use Kerdi but always go over every seam with aqua defense or some other brush/roller applied water proofing. I do what my 30 years of experience in doing tile work tells me to do even if its not what the manufacturer states. I have done many things that the Representatives say its not by the book but they have admitted to me they would trust my methods over what they have specified . Anyone who has ripped out bathrooms for 30 years knows what works and what doesn't . I am very fortunate to be working in the same homes for 30 years and I get to see what my choices of materials and methods I used have withstood the years. I will always do what I feel is best over the manufactures recommendation. Most of these companies that have long warranties are not even in business anymore since I started doing construction. So the warranty means nothing. Gluing up a waterproof material with a non modified non waterproof mortar never made any sense to me but there are guys out there that think cement board and hardibacker are waterproof also. As Isaac said , you are ultimately responsible .

I appreciate your straitfordwardness. Your right. The installer has to use his best judgement. Thank you for the tests. Very informative.

Awesome job thanks for doing this test

Just makes me happy to see people trying different systems on there own dime and time!!

Ah, yes. A rebel, a disputant, a contrarian. A position I admire and understand. 👍

A wood float is really great to install the liner vs a blade.

You did great job man, for matting and corners I don’t use adhesive, just liquid rubber and when is ready done, two or three coats on all surface.

Great video man all around keep it up I'll keep watching thank for the information

Those taping knifes can be pretty sharp. The seepage is happening on those seams. Could be your perferating the kerdi slightly when running the taping knife . Just seems odd why it's only happening in the corners and edges.

I'm an engineer so I'm approaching this a bit different. I noticed that you didn't make sure to have thin set totally covering the wall to floor seam. I also remember seeing one of your videos where you tested Kerdi corners in a cup by themselves and compared them to 2 competitors. The kerdi leaked and the others didn't. Those results make me think that the kerdi isn't waterproof itself. It becomes waterproof in conjunction with the chemicals from unmodified thin set. Would love to see a follow up video where you be sure to get good coverage of thin set in the corner between wall and floor and see how that goes. If my theory is right, no moisture.

Thanks Isaac, great job as always

i appreciate the effort to do this test. as a student of construction, i will never trust a seam system period. its only a matter of time. i would only do a one-piece or liquid membrane but that's me. i know why he did this tho. he's telling you to study old homes and how they there constructed. when you tear down enough stuff, you will see what worked and what didn't

I do have to say that the information provided by this young man is invaluable, I have learned so much in a very short period of time. I can’t thank you enough for really wanting to take a look at your own practices. Greatly appreciate you

Likely a bubble in the band somewhere, my first experience with Kerdi, probably 2003ish, the rep lined a cardboard box on the shipping guy’s desk at a local tile store, sat for a week, bone dry. Been using it ever since, zero failures. No shower sees 7 days of standing water anyway, let alone 10 minutes. I do not trust laticrete, always used proflex to set, ditra set for tile, now Allset. JMO

Should have put the band first then the wall piece goes over that.It goes floor band walls so everything overlaps.But it works that way like you said because you won't have water sitting for a week.I have been doing this for 40 yrs and find the kerdi systems reliable.Good job guys!!!

Awesome Video going through your process and your final test and analysis of the test pan

Awesome test . I like to redguard the seams . So it’s 100% sealed after using schluter .. your videos great proof that schluter is overpriced and overrated .

This was a good video. It would be cool to see performing performing same test on other systems like Wedi tile system to see their results.

That’s why you take the band to the corners then overlap the corners last . You stoped way short with the band. Just for future reference. Kerdi will not let in any moisture whatsoever when done right

That a great test thank you! The way I do it is i wrap it on the wall, so that its a solid kerdi piece and theres no seem

I use this stuff quite frequently. I don’t use that seaming technique on the corners or up the walls. I cut a wider sheet of membrane or join two pieces down the middle overlapping 2-4 inches running the sheet up the walls 8 inches. For the inside corners I cover the membrane material with thin-set and then fold the material tucking it in to the corners and folding it into a miter. I squeeze out the thin-set and hold the corners in place. I made some wooden corner blocks to hold the membrane folds in place. I weigh the wooden blocks with bricks and push them into the corners so when the thin-set dries it leaves a tight inside corner. Tiles nicely. Makes a true unbroken pan. This way you minimize breaks in the membrane.

Thank you Isaac ! I have drawn my own conclusion and I will share in the case that others feel the same way, I do not Trust kerdi completely, so I’ve in past and current kerdi showers I use hydroban on all kerdi seems, I have 1 more kerdi shower to build this month and I will be steering away completely from the system, this choice was my own professional experience, I will continue to mud my walls and deck mud over a vinyl pan , thank you for the video

Thank you for this post. I'm a tile setter in NE PA and these new Styrofoam waterproofing systems are starting to become requested. I absolutely needed a good video to share on how expensive it is and just how waterproofed it really is.

Issac, thanks for always making your videos. I’ve watched a ton of your how-to vids as well as videos you made about installs that didn’t work. I really appreciate your honesty and dedication to your craft. After every method you’ve you used can you tell us what your favorite method/product is?

Great video man!! I have 35 years in the field doing mud work both mosaic and slab installations my company has torn out several of these products mostly due to bad installer mistakes or skipping steps or wrong application. Almost every time on a shower failure it is because of plugged weep holes. This is the reason why I use the same application on everything always hot mop always floated. You have good knowledge and really good KZfaq channel man take it easy.

Does this Makes you second guess all the previous installations you have done Isaac? I mean the test is extreme, no shower has standing water for 7 days (es there is no slope etc)....Perhaps the unmodified thinset dries too quickly and it cracks? Or perpahs because of the membrane layers it does not fully dries...... What about using a thinset that has a little polymer? or use an unmodified and add some polymer to it

I love the videos and appreciate all the work One thing you might wana try though is making the pan longer so it can roll up the wall and then where you do the patches also roll those up the wall, then put a strip on the joint, and then take the wall membrane down the double up to the bottom or even down into the pan with its overhang

nice job i appreciate it the membrane isnt intended to hold that ammount of water but it shows another interesting fact ...the membrane holds doesnt dry im wondering could this become a mould issue over time once packed and tiled.Id like to get your thoughts on that ..awesome vid though thanks

Schluter states that all seams are supposed to be overlapped by 2" which you did everywhere except where you butted the kerdi band to the corner pieces. The kerdi band should overlap the corners. The leak very likely happened at the seams that weren't overlapped.

Like to see that with Redguard or other waterproofing systems.

I always over done everything I make. I’ve only done one shower and that was 15 years ago and it’s upstairs over plywood. Perfect so far. Recently we redid all the plumbing and I could see under the show and behind it. No sign of any leaks. I never heard of any waterproofing membrane at the time so I didn’t go that route. Getting ready to do another one of our bathrooms upstairs this time I will Redgard everything including the floor.

Good video man !!!

The biggest problem I have with this system is that the inside corners at the bottom have three layers. I spend a lot of time getting my walls plumb. using this system at the very least you will get a quarter inch bow at the bottom which makes getting your walls plumb a waste oftime and you will have to build up your thinset like crazy to fix it as you go up

This system, i feel, is great in conjunction with waterproofing( redgaurd, aqua defense). Never had an issue, i like the test you ran, effective.

Not boring at all brotha many thanks 👍🏻

Great Video. Please do this with the WEDI product

One thing to think about is the corners should go on last. View it as flashing on a roof, putting the band on afterwards creates a lip in which direction the water is flowing. Similar to if you have to put a seam in pan liner you always want the lip to where the water goes over the seam and not running into it.

I'll stick with pan liners and wedi pans. I hate how kerdi has so many seams, you rely on thinset and it's not repairable....If you damage the membrane when trying to replace a chipped tile then it's game over....gotta redo the whole thing. You can easily cut the membrane when cleaning the grout lines with a knife and not even know you did it. Wedi pans are 100% waterproof. It remains waterproof even if you puncture it as long as you don't puncture it all the way through. The down side with wedi is that it relies on the polyurethane sealant to waterproof the seams. Pan liner is the safest bet.

This is why I'm afraid to do a pan. We can send a man to space but can find the perfect material for these pans. Great job and much respect for your business and honesty. This is a small percent compared to all the ones you have done that came out perfect.

Great job thx for the pan test info

Run your base piece of Kerdi up the side walls 3"-4" and you eliminate that seam.

The result of 7 days flood test is great but, I still feel very unfortunate with too seams, cuts. I think it's best with only one sheet of Kerdi and the corners is folded (no cut).

You may want to try Durock Cement Bear coat it is a water proof membrane troweled on.1 part Portland 1 part bear coat it is a moisture barrier.I am a stucco plasterer applicator up in Canada Toronto home of Durock.We normally use it on vertical walls before applying foam EIFS SYSTEM.Ive done a few experiment on my own home. One example I have a interlock patio I covered over top with this product then built my raised deck free floating with deck blocks on top now all is exposed and I'm talking long winter snow and rain.3 years now you can't remove it off the interlock if you tried only with a grinder.cheers good videos I enjoy learning new things.

Thats why I only use Kerdi. It took 7 times longer to get a fail. Great job on the test. 👍👍

That small amount for 7 days "standing" water. I'm cool with the results. Any water to the structure?

Perhaps when you were flattening the kerdi band strip you put a pinhole in the corner with the trowel. I use a grout float with that stuff....just my thoughts on why you had a small amount of water in the corner

The water penetrated at the point between the prefab corner and the kerdi band where it did not overlap 2" like the instructions say. This is a good example of why you should follow the manufacturers instruction to the letter. That said, doing it the way the manufacturer says makes the corners way too thick, but that is the reality of the matter. Thanks for doing these videos. If you try again, install the band first, wall to wall and then put the corner on top. That way you have your 2" overlap at all points. Thanks again Issac.

Dude you are the man love this video! I have recently been using regard to bond all kurdi band to corners. I paint the redgaurd on with a three inch chip brush the I lay the kurdi band in my corner. Then paint another layer over the top. When I come back in the morning everything is dry and super tough . Maybe. Just maybe you could test my method ??? Thanks again videos rock!

It didn't look like you had a 2" coverage from your tape band over the corner piece in that corner when you installed your wall membrane. Was this also the wall where you had the bubble form?

Its hard to get a perfect seal and considering how long the water was in there it did pretty damn good. If that was flooded for 7 days that would mean there are major issues at hand like the whole house has flooded

Does make you question all the money spent on this system! If it wasn’t so damn readily available everywhere, 😆. Great video!

Great Video!

This is why you shouldn't fix something that isn't broken. If you know how to build a shower that is truly cementious and has a mud/mop based shower floor it will not fail. People have been doing this since before the inventors of schluter, kerdi, durock and all the others. Allow your shower floor to "breathe" the water as necessary. You should never be worried about standing water for any amount of time, regardless of any conditions. Tile/Stone install is very complicated, unique, and a high liability. Why try to save $500-$750 to hire someone who might not be qualified vs. a company/contractors who actually were doing it before the styrofoam/drywall stuff came out? Tile doesn't lie, and who you hire will directly reflect that.

Great test!! my only thought is that Im not going to line my pool with kerdi!! lol, BTW, I dont typically use sheet rock for any backer! My belief is that if you had used Kerdi board and kerdi pan and just Kerdi band would have been less time and less seams = less possible failure!

I typically block (as in drywall finish work) the layers and joints etc. Looks like a good practice.

Great job. Thanks

What about a test with the kerdi/schluter thinset? I have been thinking of doing a basement shower/bathroom and thought this system was the way to go.

Only thing I do different with Kerdi is I would lay the floor and then the preformed corner and then the walls , like step flashing

I'm a home DIYer and I'm in the process of replacing my fiberglass shower. I'm using the Schluter kit mostly because of the pre-sloped pan and drain. Couple of things, code here in GA is no drywall what so ever in a shower, if your test was done with backer board do you think you'd have the same results? My thinset was "thin" but yours looked like leveling compound. I did check the bond and it looked good and I had no leaks after a 24 hour water test. Hope the bond I got is strong enough. 7 days does seem extreme and maybe a little misleading, if you had tiled and caulked the test bed I would think you wouldn't have found any leaks. Also I used a wide plastic drywall knife to lay in the material, didn't want to risk using a steal blade. Great job on the video.

What is your personal preference in systems? If you do mud float walls, does it stop water any better than kerdi? I always figured that because kerdi is waterproof, once water does get behind it, it cannot escape. Thoughts?

This is an awesome video! There was no overlap exactly where water got in. Bend was shorter and didn’t overlap with the corner. As you said... you didn’t want triple overlap, but that resulted in no overlap in that tiny section. I think you wanted us to figure that out :)

Is it possible the trowel edge poked a hole in the band when you were squaring the perimeter/edge? Journeyman 42 years.

Nice test What kind of system or materials you recommend for shower wall and base?

Great video. This is why I only use chloreloy by Noble.