*Feel free to discuss amongst yourselves..Issac's video was flawed since he used a mat below mortar bed which gave a false result..., I have stated my opinion on this subject many more times than I care to, I have done a demo and stated my opinion again on all the aspects of a pre slope, it's a dead horse now and I won't entertain any questions or debate the subject here*
Well, what you DONT do, is apply caulk while screwing the cap on in between, which is what I did. Ow I can’t sleep thinking that there’s a shower I built, just waiting to fail.
I love tile drama lol! All of you main guys putting out videos are awesome! I applaud you all. Being a contractor myself I don’t have the nerve to do videos so my hat is off to y’all!
I've been studying all you guys for several years; you, Diblasi, Ostrum, and others. I base my common sense off of the calculations of all of your condensed wisdom. I choose to do a preslope. I don't seal the final pan top until after I've done the water test to ensure the membrane is working properly.(when you do your water test, you're gonna saturate your pan no matter what. The water is going to seep up through your drain barrel threads and weeps holes.) So after the membrane test passes, and I let it dry out for a couple days, that's when I will liquid membrane the top to seal it for the tile setting. Sure, a drain can back up and still flood your drypack,but generally speaking, all water should egress out and not backup past the p-trap. This is the process I've come to use as my ritual. I appreciate all the videos all of you make for teaching us what does and doesn't work. Keep the Info flowing!
Very interesting! Years ago and still in my country we didn't had shower pan liner or preslope. We used construction plastic whether it black or clear and for all them Years our showers never failed! I lived in my house for 38 years on a no slope shower made with construction plastic and never go a water problem! Thanks for reiterating the old days!
Why is your country not named ??? is it classified Top Secret ? Is it because no one has asked ?? Ok, What Country did you for 38 years only use construction plastic, either black or clear. I think that the plastic is from Alien Space time. please send a photo of this amazing plastic sheeting , thanx.
Interesting experiment. Thanks. Most amazing part was the amount of work done inside the house. I kept expecting to hear a wife coming in the room and screaming "what are you doing in my dining room?" or something to that effect.
Thanks for your videos. After many tiling videos, yours always prove to be the most informative. You give peace of mind in areas where I feel I might have made a mistake. As a long time handyman, I just did my 3rd shower pan in 15 years. On the latest, Worried about my pre slope being enough. just put to rest.
You’re the reason I tried without a preslope. The logic was there. I worked with an environmental engineering company for years and knowing how chemicals travel underground through soil and other natural (and unnatural) channels the preslope argument made sense- how could it matter if the water moved through capillary action?!? So watching this was awesome and I appreciate these videos.
I agree that the issue is not that the dry pack itself clogs the weep holes. However, isn't it possible that over time, with the addition of detergent residue, mineral deposits and perhaps mold, the mortar (in the weep holes) eventually becomes less permeable or impermeable?
Whether you pre-slope or not the mortar is not ever going to dry out in a shower that is in daily use. With the tile cap, water will not evaporate beyond what is held by capillary action. With tile on top and water just seeping through the grout, there will never be enough water flowing through it to wash out bacteria or mold.
I have been a flooring professional for 30 years. You my friend are a critical thinker and what you are explaining makes absolute sense. The question now is " how saturated do you want the mortar bed to be"? You have my attention.
Wet is wet...capillary action insures all pans ( water in water out system ) will always remain wet in void of air to dry out. Going forward we all waterproof the the surface now, be it liquid topical membrane or a fleeced/clothe... Keeps any moisture out so the pan is only for a slope at surface.
@@StarrTile Im pretty convinced that keeping moisture out of the mortar bed is the answer. water needs to go directly to the drain without absorbing into surfaces period. Water needs to escape before it can gather or absorb.
@@gwynja3191 Glad someone mentioned this. I was going to suggest that Isaac, mentioned in the video, uses a membrane over the drypacked pan (please correct me if I am wrong). Wouldn't this be the best practice.? This video is very eye opening and appreciated!
@JoeySchalger @G Wyneja3 someone posted this in the comments, since you missed the entire point of his demonstration. "Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains"
You and Issac both have great content. I have been learning a lot from you guys and now feel like I can tackle my own shower pan. I hope one day you guys will be able to come together and collaborate because I think it would benefit all of your guys subscribers. Great stuff.
Perhaps there really is more than one way to skin a cat??? I watched both videos and still cannot make up my mind. Inconclusive. Someone mentioned in Tile Coach's video about making/using boxes made out of plexiglass. That would be definitive. To see in real-time how the water is moving and traveling. . . Gold! In this video we never quite know how much water is sitting at the bottom from the pre-soak. In the Tile coaches video he used some cover at the bottom...
@@johnsnetsinger7105 Depends on your definition of what *collaborate* means in YOUR head. Both Bob and Issac had a joint live stream event together so you can decide for yourself. Additionally, people can change their minds on certain products or techniques as more information and data becomes available. For example, the Earth was once considered *Center of Universe* and that everything circled around the Earth to appease the Roman Catholic Church and later Galileo (Italian astronomer) correctly asserted that our Earth circled around the Sun and was persecuted for it. Even Issac has now essentially stopped using the Schluter drains (both circular and the linear drain) since they have had many failures and since switched to preferring the Fx Flow drain which seems to be much better performing drain. Lastly, even Issac has said there is enough room in TH-cam to have lots of tiler slingers on the platform and it is not a contest where it is either Issac or Bob.
I know this vid is 2 years old, but it reminded me of an experiment back in middle school. If you take a stalk of celery and put it in food-colored water, the stalk will suck up the liquid far above the lowest point of the container. It’s an easier visualization of capillary action. So no, water doesn’t always go to the lowest place.
Slope or no slope. That is the question. I've watched both videos. Both to me look fine. But if I was to err on the side of caution, I would put in a preslope. Just for peace of mind.
The thing I see, is the pre-slope (just like the no slope) requires 100% saturation to work. Both you and Issac showed that. But if just one cup of water was put in at random all around, how much would leak back out? Putting on a layer of tile with the correct grout (by a professional, not an amateur like me) means almost no water will get in. Yes grout is porous, but done right it would only be "dampness" that SLOWLY gets through. All the shower water will run over the surface and down the drain. Like you said in your 2014 video, for the water to be able to actually run down a slope while covered in mortar/dry-pack it would have to be absolutely saturated and if THAT much water is under the tiles, then something is badly wrong and the entire shower floor will need to be torn up because grout and thinset will start crumbling.
Every shower I tear out with no preslope, smells terrible, which is caused by bacteria, this is my main complaint. At end of day, if water isn't leaving the pan and destroying everything, you are good(ish)
wow Ive always done a pre-slope but I think Im convinced, I will definitely try to avoid doing them. Water always finds a way I guess. still its the Gravity pulling water down creating a drier area near weep holes and that drives the capillary action .
I posted this over at Isaac Ostrum video comments and curious what your thoughts are? A Case for Non-pre slope Just being the devils advocate here. First off I always put a pre-slope in my work due to avoiding any future liability but I don't think it's as important as we make it out to be. We need to keep in mind that the porous deck mud acts like a huge monolithic coarse sponge. Any monolithic material composition with particle sizes below 0.100" or less than 1/8" will have capillary action and will hold a "perched water table" at a certain level. I don't know what that level would be for deck mud(would be a great experiment as well) but it's there even if i't a 1/4". In a gardening container pot with the average potting mix you could have a perched water table as high as 3". An example may help. If you soak a long sponge in a bucket then hold it vertically letting the excess freely drain out and let stand for a while you will notice that the top is quite moist but if you squeeze the bottom then water pours out. That's the perched water table. Even with no pre-slope there is never any "standing water". I have never found much "standing water" in these demos. There may be some free water but it's mostly due to large cracks losing it's monolithic structure and or a large negative slope but not directly due to no pre-slope on a flat floor. Any water higher than the PWT is drained out of the weep holes. Moisture above the PWT is held tightly to the particles by capillary adhesive forces.
I appreciate your insight at explanation.. Perhaps others will benefit by it. It is interesting to me that you are the fourth person to comment that you do a pre slope in order to avoid liability, I have yet to pull out a saturated smelly shower, or even one that had cracked from the constant water presence that was less than 5 or 10 years old, most have been in excess of 20 years plus that were Builders grade and many of the things were done incorrect. If I ever thought that not having a pre slope would lead to a failure in a year or two then I would definitely be on board to do them, it is just not the case
Thanks for the experiment. Since you saturated the pan before the final test, all of the water came out since by definition, a 'saturated' pan cannot hold any more water. What we don't know is how much water did it take to saturate a flat pan vs a pre-sloped pan. And as Isaac says, is there a puddle in a corner that might have held less water if there was a pre-slope. And maybe a pre-sloped pan would drain in less than the 12 min it took for yours to drain. Just continuing the discussion. By the way, there is gravity all through the pan and the mud; it's just that capillary action can overcome the gravity for a portion of the water.
@@user-xt1vs2oz3b Yes I agree. If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo.
I have built many pre slopes using 22/32 plywood cut to fit over the shower sub floor. A 3/4 riser at the outside and 2” drywall screws around the hole cut to clear the drain will provide an almost perfect slope to the drain. Good demo, thanks man!
I have seen guys do it with ¼ cement board, blocked up at the outer edge, and screwed into the floor at the center, with thinset to the up the slope under it.. the screwed once that's set. I'm not brave enough to try it, but it's clever, if nothing else
I do not use pebbles and use the plastic disk too. So I agree on the point. Although the issue with no preslope is to help water from pooling in the corners of the pan or the low spots. This video shows those low spots. Now the issue is mildew growth. I have seen it on ALL non-presloped pans. All the corners will have mildew growth from under the tile and can never be removed. All of the presloped pans do not have this issue. Sure not using a preslope is easy, drains 90% of the water, but mildew growth in the grout lines is a major issue with this. This video is a prefect example of water pooling in the pan. All the water would have drained if there was a preslope going all the way to the drain. The mistake is Starr just props up the edge of the pan not the whole pan.
May Take 12 minutes without slope maybe with slope take 6 minutes byw u are a great tile master I like see a nice work done bcz i know isn't easy task to complete without years and years on real work field I know what's I talking about bcz I'm a plumber after 25 years I still learning from other trademan 👍
I still believe the preslope will allow more water to find its way out , however i am going to waterproof my shower beds to reduce the amount of water that makes it into the shower base, and hopefully reduce mold build up under the floor tile
When I did my first shower I did a pre slop mainly because I did not counter sink my drain like you do. So since I had to bring the floor up to the drain I did it. Like you say it couldn't hurt. But I also believe it is not necessary . Especially if the liner is installed correctly. Keep up the good work.
Everyone waterproofs their shower nowadays, including the pan surface....so no water gets into pan, so preslope for what reason exactly ??? 😂 Gotta think about things rationally
OK guys. First I'm not a tiler, remodel expert, builder. I am however a stickler for doing things right regardless what anyone wants to do. In my opinion both of you are right. I've watched both of you do your thing and you both seem very competent and skilled. I like watching Bob, no offense Eric. Bob states he is in this video thing to help people like me figure out what to do and what not to do. He takes time in his videos to explain (sometimes twice or more) what he did and why he did it that way. Makes perfect sense to me. He works alone running his own business and I expect being in Atlanta has more work than he wants, perhaps not. Regardless if where you live and work requires a permit and strict adherence to building codes then you do what you have to do. If you are reputable and do good work, back up your work with your reputation then you should never have a situation where the client is "out to get you". Now some might say that those building and zoning people don't know crap. Well, they are the customers best hope of making sure his job gets done according to some else's guidelines and requirements thereby keeping professionals or semi professionals honest. In Georgia, where Bob and I both reside, there are way too many folks out there running around claiming to be something they're not. Which makes finding a pro somewhat difficult because ultimately the customer really doesn't want to pay anymore than a fair price for quality work and materials. Eric, You run your own business with employees, that means you not only have keep track of what you are doing but what they are doing as well. I'm not advocating that your folks are not trustworthy or skilled in what they do, but I do know first hand that "when the cats away, the mice will play". I've learned alot in my sixty nine years on this planet and I am proud to say alot of it was because I pay attention to detail, after all the beauty of any job done right is all in the details, Bob pays alot of attention to details and makes that clear in his videos. I have a small project I am considering right now, I know how to get started, but if things go badly or not I am working with obsolete no longer made tile. So I may call you Bob. Good luck to you both, I just had to chime in. It's my opinion and I'm sticking to it.
I appreciate the effort as much as anyone else but people should realize neither of these tests actually prove anything. Doing science is hard. One of the most important parts is having peers poke holes in your methodology. Here we have one test essentially testing the vaiability of a funnel. A plastic funnel with mud on top. Of coarse it works and you'll get all your water back. But that's not what your testing. Your testing whether its necessary over a non sloping funnel with mud on top. To that end it tells you nothing. On the other hand you have the non slope plastic funnel. That was saturated before hand. Look, its not exactly a huge leap to realize that there is no other possible way for this to end then to get every ounce of water back. That is what saturating is. 100% of the space that could be filled by water..... is filled by water. Where else could it go? You could've built big pools under the mud and you'd get the same result. You've already filled the mud and dead spaces with water (the fact that there probably wasnt any low dead spaces is irrelevent. If there was they would've been filled little pools with the same end result.) Neither addresses the actual issues. Im not trying to be a pro skeptic here but the issue is a lot more nuanced and difficult then this. As much as I loved mythbusters their methodology had the same issues. It wasnt science. It was just science influenced experiments. You could literally spend 4 years majoring in the ways experiments can be conceptually flawed. Researchers still get disgraced to this day by having their methods shown to be subject to basic biases.
I agree with this statement :) in the end there maybe a small influence of slope (gravity) if there are pools (gaps) in the stratum but its likely quite small. Since the influence of slope would be to increase the speed of the capillary action and time is not part of the experiment in a meaningful way... I am not a professional, so feel free to ignore my comments. I am a DIY, with my own bathroom remodel :) My take away is - slope the pan to assure efficient draining, redguard the pan to reduce influx to the pan, choose/maintain low permeating wall board, tile and grout.
If a serious amount of water is getting to your mortar won’t it just absorb it and slowly weep it out regardless of whether it is pre-sloped or not? Unless a small amount of saturation in the bottom of it somehow damages the drypack it seems the pre-slope is more of a precaution against a poorly or improperly installed pan-liner making it pointless if it was installed correctly in the first place. Just my two cents.
The only real advantage to having a pre slope is if your subfloor is off-kilter and you don't Rectify that before the pan material, then a pre slope would benefit you
If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those low areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo. The pea-gravel is for long term use, it will work sort term without it. Those two dozen small holes with just deck mud around them would soon get clogged from deposits. The gravel greatly expands the area taking longer to get clogged.
I think the issue is also the fact that by the time you are relying on preslope to drain a saturated pan you have a significantly bigger problem on your hands and a failing shower. Preslope or not it's failing.
And how is that? Before liquid water proofing there was nothing standing in between. I can tell u rite now 99 percent of showers leak right threw the grout into the pan. And have been functioning like that for years upon years without the floor caving in or whatever you think might happen
I suggest we do comparison experiments for saturated pan with/without pre-slope to see if there is a difference in the amount of new water that replaces old water. First let's use water with certain concentration of ink to saturate both shower pan mud beds, then use clean water to 'wash' the mud beds to see if there is a difference in the color of water coming out of both mud beds...
That's a great idea and an experiment like that would be the only way to truly know if water is cycling. Having said that it's a moot issue because everyone waterproof their pan surface now so no water gets in to begin with
If water gets into your mortar bed which is mortar then how is it that it cannot get into your clogged weep holes that are clogged with mortar, irrational 😂
Just a word out there for all the Tiny House [on wheels] DIY builders -Pre slope the shower, because you KNOW the trailer supports are going to sink 😉 Great video! I like how all your videos are thinking videos. Details matter for sure & the solid pebbles blocking weep holes makes sense.
Both ways are fine if your plywood is level or you seal the deckmud top with redguard or a waterproof membrane. If its not then you could have a small pool of water sitting in the pan low point which is why the code required the pre-slope under the PVC.
Why not do a pre-slope?? I don't understand why it's even a debate?? The cost and labor of doing a pre-slope, is nothing compared to the cost of the entire job. Please, if you ever do my house, do a pre-slope. I'll pay the extra extra change.
Plus.... Assuming that's a 2' level, it's only an 1/8" per foot. When you add the second shim, then it's a 1/4" per foot. You're trying to convince everybody, based off your opinion. Why?
Mainly it's a moot issue nowadays because everybody is waterproofing the top of their pan material, a pre slope will be insignificant and irrelevant... But as I mentioned in the video, your pan is 100% saturated whether or not there is a slope underneath or there is no slope, breaking down the binding components of the mortar. But again, a moot issue nowadays.
Don't know if I thinking cornetly... If I do preslope and than read guard on the top than slop... Than if Wather penetrate slope.. Stop on read guard and goes down cuz preslope... Right? His with out preslope Wather gonna stay somwhere in lower spot... Please explain Thx
I have had second thoughts about this matter. If a small leak was to happen in the bottom of the pan were the first water collected then that water would RUN OUT the leak and then that water would be topped up by the next shower, repeatably. With a preslope all water would run out and only a minor amount of water would be available to leak through. So if that is true then the matter to be faced is if anything goes wrong with the pan liner install then the potential damage below is minimised. With a flood test the water pressure above would push down on the pan liner minimising leak flow. the empty tile bed would not exert the same sealing pressure. So both tests work but the long term out come from the failure of a less skilled installer may be minimised by the preslope. I am about to do a second bathroom, the first i did years ago without any water proofing on a ground slab with a slope to the outside. I 'lucked out', no damage inside. I just followed the old trady's advise at the time. This time upstairs no mistakes.
Removed a 30-yr old shower in FL. No pre-slope and no sitting water on the liner. No water-proofing of the mortar bed top either. The drain base was resting on top of the subfloor, 1/8" above it. That's a data point supporting his claim.
What I do, is that once my drain is set I will use scrap pieces of 1/2 cement board and install it in the shower floor around the drain. Than mix some sand mix and do a small pre slope. Just so that I have a pitch towards the drain. I try to avoid having a big shower floor. The big step up will be a negative on my customers. What are your thoughts?
Does the mortar adhere to the rubber underlayment like glue after it dries? Or after the mortar dries and shrinks a little, would it be possible for some space or gaps to occur which then the pre slope would always be aiming that residual water back into the drain?
Hi this is nice testing but it is not in real life testing. First you supposed to build the regular size shower not 3 by 3 feet shower. If is smaller water can penetrate much faster and easier because the distance to the drain is shorter. I think it is depends where you have the drain. If you have linear drain 4 inch from the wall you probably need to do that pre slope because water can set across the drain wall if you don’t have the pre slope. This is very good question you need to have it pre slope or not.
So you measure a 1/4in at the end of a 2ft level and call that correct. You just said there should be 1/4in slope per 1ft length. So should you not have 1/2in at the end of the level.
I learned to mortar the shower with slope without the clamping collar on . Then install a shower pan. Then idk what the tile guy does after that. Which makes sense, like a water slide to the drain.
It’s not just capillary action, it’s hydronic pressure, the pre slope is just for incase but with that said, water won’t wick to the pan just because. Experiment is flawed. It’s not the end all of you don’t preslope but over time you can end up having an issue a extra 30 minutes can 100% prevent. The mortar bed is porous and if it is to get completely saturated and make it to the rubber liner then there’s a good chance it’s not goi g to come all the way back up thru it or wick it’s way to the drain
I think the first water in goes to the bottom of the motor bed and stays there forever. new water, coming from next wetting events, never mixes with the first water, it simply goes down to the the permanent bottom water and that new water flows off, out the weep holes. It does not ever mix with the first water. In fact in the ocean, water layers can remain permanently separate. Military submarines hide under these layers of water, but i digress. In fact soils hold water for years. In Australia, old roads, 20 years old or older, they have dug up have soil moisture exactly the same as the day the were built. even in very dry areas with drought being a regular thing and very low water tables. Great demonstration. intuition can be misleading.
I've been doing residential demolition/renovating for 8 years now, every single bathroom I've ever taken apart has had water saturated in the pan liner. I have never seen anybody do a sloped pan before the liner except on youtube.. It makes way more sense though if the liner is not sloped how does water drain out properly.. I watched your experiment but with daily use you are going to have alot of water sitting there and it will not dry up as fast if there is tile and grout on top.. Sloped pan will be more hygienic as you have fresh water being introduced and shed constantly
My only argument is that the measured water that you added just displaced the water that was already in the pan. The excess just ran out the bottom, plus the newly displaced water, which is why it is equal to what went in before hand. However, the water in the bucket after the experiment is not the same as the water that came out of the bucket pre experiment, not all of it, granted there is no way to tell how much of it is the experiment water, or presoak water. The only way in my mind to truly test this would be to weigh the mortar mix before adding water and then again after you soak it, to determine how much water this thing is actually holding. If you were to take the pan out of the pan liner you would see that there is water left in the bottom of the pan liner. There has to be... granted this might not happen on a preslope, but either way I don't think it would be enough water to matter. Just my thoughts on the experiment.
I totally agree with this comment. 30 year GC here and I don’t understand why you are so stuck on proving a preslope doesn’t work. I found your scientific experiment flawed. The very fact that you didn’t measure the water from your very first pour to saturate the pan tells me that water could have been sitting in the pan as this commenter pointed out.
If you don't waterproof your pan surface, which by the way everybody does now so it's a moot issue, then you're always going to have a water content in your pan, a my experiment I was replicating that water content, if I had started out with a dry pan then obviously the same amount of water coming out would not measure up to what went in. But to the bigger question that you propose, why am I intent on disproving a pre slope functions as intended? Well you just kind of answered your own question I am proving that it does not function as intended, people are brainwashed into believing that it works, in the void of gravity then capillary action kicks in making it impossible to function as intended... it would only work if there was no mortar, like drain lines do. I know it's a little bit like finding out the Santa Claus isn't real but a lot of people still believe in things that aren't true
@@StarrTile I think that you prove the point supporting pre-slope when you added the half-inch shims. The water that was stagnant on your pan lining was displaced when the shims were installed. (Simulating pre-slope)
I don't understand why anybody would believe what Isaac has to say anyway, he has eight or nine videos of his failures.. and just like you said he cheated on his experiment so has zero credibility
to my understanding, you said the soapy shower water deteriorates the sand-mortar mix. It deteriorates the cement components and leaves the sand behind. So anytime water gets into the mortar mix is bad? Is this correct? or is it ok for the mortar mix to get saturated? I realize that you use thin set around drain and you mention it helps the redguard waterproofing to adhere better. that was said in another video of yours. then you coat with redguard. This is to ensure that water never actually enters the mortar bed but it is there as a backup? This is my understanding of the video, am i understanding correctly? This is very helpful to me.
awesome video.... so I saw a video of you applying Red Guard... is this where I would apply it ? onto the mortar ?and then after 3 layers.... next is thinset for tiles ?
@@StarrTile would also like to ask you about the type of grout to use on floor tile in the shower floor. should we be using epoxy grout or something else ? TIA
Can I ask, the major thing I see different between you and other shower guys is you waterproof UNDER the mortar bed. Many others do the bed right on the slab or plywood subfloor, and then they waterproof overtop with membrane or whatnot and many of them NOW (after I presume watching you) they almost all apply a waterproofing like redguard or it's equivalents ontop of that. If the redguard or whatever is the end all why do the waterproofing under the bed? I've even seen you use membrane instead of a liner on tricky showers before your mortar bed. I'd like to see that test, do you need to waterproof under your mortar bed. I suppose in the end if all else fails it's one final redundancy but you tend to shy away from that besides this.
The shower pan liner be it CPE or PVC will not last forever if water is sitting on it. Just like everything else overtime it will deteriorate and eventually fail. However for every shower pan liner you put in without a pre slope it will fail in probably 200 years. With a pre sloped the shower pan liner will fail and 350 years. In other words, you will be long dead, as well as the original owners, and there will be nobody to sue when the pan liner fails, and pull more importantly when the building is resold with the warranty as is. With the building industry today, buildings don't last that long and neither do bathroom since they are remodeled every 15 years and rarely will a bathroom make it 30 years. This is why in my state of Michigan they eliminated the pre slope in the building codes because it is just an extra expense that's a needless to the homeowner.
Jeff D Living in a condo complex on the second floor?, I demoed a 60 year-old shower because I was afraid the shower pan had failed. No cracks in the tile, leaks onto the downstairs neighbor, or anything like that just OCD fear of liability claim. Absolutely nothing was wrong with it. Even the membrane was in pristine shape!. Chicken-wire tile too by the way....uuuughhhhhh!.
Okay, most interesting demonstration but the comment at the end is most relevant to me: "most tilers are...waterproofing their pan surface". That's what I'm struggling with. Someone please explain why anyone would build a shower pan out of a porous, unsealed material. You wouldn't install a toilet or a sink that's porous to water.
Bob why do you redguard your whole sand and cement bed in other videos if your no preslope is the way to go. Looks like the weight of the sand and cement made the center lower somewhat giving you a preslope
I started waterproofing the entirety of my for a couple of years ago, that's why the whole notion of a pre slope is a moot issue, but Isaac had challenged me after he did his video so I took him up on it
In Memphis a preslope is code. There is a shower pan inspection prior to being able to start a shower that checks for proper preslope & pan installation. It’s code! That’s all you need to know bottom line. “If all else fails read the directions”(Preslope is part of the directions for shower pan installation). And lastly, what’s the number one rule of plumbing...Water rolls down hill😂.....BTW, 30+ years of being a tile contractor in the Memphis area.
Water only rolls down hill in a gravity induced environment , that quarter inch per foot is a plumbing code for sewage pipes, it doesn't work that way with a 150 lb of mortar capillary action will take effect... your pan is saturated with or without a pre slope. But the whole notion is a moot issue anyway since most people are waterproofing the surface of their pan
seems to me "capillary might be better than gravity" BUT "capillary PLUS gravity" might be even better ..... I suppose no slope is not a critical flaw , they've been done like that forever , but maybe a little slope is just a little added extra benefit , not critical , but just a bit better , can't hurt .... That's my take on it
Interesting video. But wouldn’t having no slope at all cause some water to pool on the shower floor without any way of being evacuated other than through evaporation?
Wicking action would ensure that your pan would be wet all the time, the fact that there is no gravity because you're dealing with a mortar bed that gets saturated would not allow water necessarily to pull anywhere, all that being said it's irrelevant now because we waterproof the surface and thereby the mortar never gets wet
Bob, here's something that occurred to me re the experiment--whatever water there was that wouldn't drain from the pre soaking, would cause any additional water to exit---because the space for static water's already taken up. I wonder if a better test might be to do it by weighing. As you said a little water will remain and that, I think, is the problem---it would never drain dry-- it' would always just sit there (though it would be replaced by the new water, of course)---do you see what I'm saying on this? It would never be dry and I'm thinking it would foment mold more quickly than with a presloped pan. What do you think?
You are correct, there would always be one hundred percent saturation, but the theory of new water taking its place is flawed, all the water doesn't know to evacuate when new water comes in, plus the new water is Tainted by the person being in the shower, the theory is that the old water has chemicals, shampoos and soaps and body scum, the new water is supposed to take its place but yet you have the same material going in that are going out.... the only way the water in water out Theory would work is if the person was never in the shower
What if you saturated the pan with clear regular water and the dyed a separate bucket with a color and see if indeed the water isn't replaced when it drains down to be recollected? . 🤔
S9...I am installing or cutting into a cement floor to have the shower tile sloped into a floor drain. Can I just place a strip of pan liner around the edges up on my 2x6 backers and extend down into the pan not putting the pan liner all the way down to the drain? Of course I will be putting thin set to smooth out the cement to put the tile on. Thanks for any input
It will only deteriorate if you don't do it right or waterproof it, you cannot use concrete because it has rocks in it and you could never get it flat and level, even if you could it would be problematic
SO MR STARR. are you now using redguard over the entire dry pack? i know at one time you were just doing like 6 inches around perimeter. what i dont get is the words " mold sandwich" i see this phrase every time someone asks can you use a liquid membrane over a water in water out system, well why isnt this mold sammy happening in a schluter type system? i guess the only difference would be that in a schluter system the water under tile is making its way to the drain but afaik thats not happening as the water just evaporates, but if it did then just dont put liquid membrane in the general vacinity of the drain in a liner system and that water would also drop down to weep holes...
It hasn't been proven since wicking action will insure pan is saturated all the time... That being said it is irrelevant now because we are all waterproofing the pan surface so now the mortar will ever see any moisture
Would an alternative pan method be sloped mortar base(no membrane) with a recessed non weep hole drain, coated with two or more coats of Red Guard with the coating continuing up the walls. Would this be the same as Custom Products preformed foam shower bases with Red Guard (but much more inexpensive)? Would the sealed mortar base trap moisture between the tile and the base, and create smelly mold and mildew? For a shower used daily, is mold and mildew an issue regardless of the pan system used? I wonder if a daily used shower pan ever dries out during its lifetime? Finally, does all the controversy over shower floors make preformed acrylic and cast iron pans the ideal shower floor? Great video...thanks for taking time to demonstrate capillary action of water!
Yes I do the same, I have a library with 350 videos and you will see me tearing out saturated shower pans all the time... but a lot of mistakes go into those pans when they are being built including not making sure the floor is level, just because there is a failure you cannot blame it on one thing alone, operator malfunction is prevalent 👍
@@StarrTile I can't understand why you are so anti presolpe? Just do it the correct way manufacturers have it in there instructions local codes call for it...give people the correct info.
@@Tilethoughts I'm against it because it hasn't been proven to be effective... I prefaced the video by saying that I never tell people not to do a pre slope, I just show them as I have here what happens without one and Isaac did one with one and we have the same result, sorry buddy I'm not a book Soldier I question things 👍
@@StarrTile how has it not been proven to work? Everything is sloped to the drain just like your finished shower floor...why not just do your finished floor level?
@@StarrTile if you so strongly believe that a level floor under your liner is sufficient please make your finished tile floor level as well same concept.it should drain just fine with your logic.
Love your videos, so thanks for sharing your knowledge! Can you tell me if my thinking is right with this approach: Using a Flo FX type drain without weep holes makes the pre slope totally irrelevant, , right? My approach is: 1) tar paper/plastic sheeting right over the plywood substrate; 2) staple metal lath; 3) build mortar shower pan with the right pitch with Flo FX installed; 4) install waterproof membrane like Kerdi or liquid waterproof barrier like Red Guard, Hydro Ban, etc. over the mortar pan; 5) install floor tile. No need for the 40mil plastic liner in this case since the waterproofing is happening on the top of the pan, right?
Yes suppose your way would work... there are many many ways to do the right thing as long as it doesn't leak at the end, I don't necessarily agree with doing it for a customer because I don't want to toss people failure. Having said that I waterproof the surface of my pan so it also makes the pre slope obsolete... and I don't need the flow drain for that
Hi, neat experiment. But I have a question. Did you seal the threads to make sure no water was escaping around that drain barrel? I didn't see or hear that mentioned. That could make a difference in the result. Next, i see in comments people saying that "capillary action is stronger than gravity". This only applies if you DO NOT HAVE full saturation in a substrate. Its called wicking and is due to waters high surface tension that causes adhesion. Full saturation creates hydrostatic pressure. Hydrostaic pressure created by gravity will make the water flow to the lowest point always. As the pan loses its full saturation state, and evaporation occurs at the surface, wicking kicks in again and will start to pull any remaining "puddles" of water from the bottom interface hence your result here. Also think about how a finished concrete floor gives off moisture from below to the surface. Its the waters high surface tension and "wicking" action at play but not when in a full saturation state. A pre-slope will certainly make a saturated pan drain a little faster, and I believe a pre-sloped pan would likely dry out a little faster than one thats not, but I think the difference would be negligible and not important to these applications. I agree with the author on all his points. Pebbles gonna do more harm than good and if your pan gets saturated, pre-slope gives no real benefit. Now my question is, since all tiled floors with grout joint are usually "sanded" grout, they will not stop water egress to the pan mortar. Sure you can seal them, but how long does that last? My question is if ALL tiled floors fail to keep water out of the pan, can the pan itself then become a "mold factory"? Now thats what I want to know. How many pans have you demoed where you saw pan mortar failure (due to constant saturation) and also how many have been laden with mold?
I've demo'd enough of these types of showers to know if your putting a new shower in your house go with a newer waterproof system (wedi, schluter, ardex, prova) every single one ive ripped out has disgusting sitting water. Pre slope does make a difference they tend to at least not have standing water. Starrtile is crap ass set in his ways and that's fine but guaranteed his shower pans are bacteria breeding grounds
I am not a tiler, but a slope makes more logical sense than a flat surface for directing water once it gets to the bottom. Now the debate perhaps should be how much pitch. Is it .25 inches per foot or .5" based on how much faster the water drained once you went from 1/4 inch to 1/2. Again not a tiler but when you mention using common sense/logic, you were speaking my language. Lol Anyway awesome video.
As a standard plumbing code a quarter inch slope per foot is great because you have air/gravity working on the water, in an encapsulated area as you have with a mortar bed gravity is proceeded by wicking action and therefore your pan will be moist all the time regardless of any type of slope... but yes, a quarter inch per foot is what they call for, having said that everybody waterproofs the pan surface now so the whole pre-slope notion is antiquated.
@StarrTile Thank you for responding so quickly. I have watched a few of your videos and will now watch a few more to understand better the differences between your preferred method and TileCoach's. I am looking to redo my own 4x3 shower which currently is on plywood with fiberglass pan and surrounds... Any specific videos you can point me to would be helpful. Cheers.
If you don't want any water getting into the bed then waterproof it before installing the tile. This whole issue is about water getting into the mud bed. If you waterproof the mud bed then a presloap is a waste of time, in my opinion. Plus you will not have the bed decay over time and mold inside the bed if water seeps through the grout.
Your 1/4 inch shim put a slope across the entire shower mockup; 18 to 24 inches; not the 9-12 inches to the drain. The 1/2 inch shims gave a 1/4 inch per foot slope to the drain, which gave you a better evacuation.
whats the big deal? seems to show it doesn,t matter either way. The mix used has barely seen any cement so not surprisingly crumbles sometimes and is very porous
I’m not arguing which is better, but in Florida a preslope is required by code. Also, a permit is required for the pan liner. That requires it to be installed by a licensed plumber. Just saying.
yes I understand what you are saying, however I have worked a dozen times in a Florida taking out shower and have never seen a pre slope, but then again there are certain States that require a boatload of things like California but yet jobs are still done wrong. And when you waterproof the entire shower including the pan then the pre slope is a moot issue and would never kick in any way so it would be a waste of time
@@StarrTile i don’t disagree totally with your logic. However, the purpose of the preslope is not just for a the water to fall. It is also to overcome the unintentional wrinkles or air pockets that may occur during the liner install. If installed perfectly flat and wrinkle free (heating it up) then probably no problem. But one cannot say that their liner is 100% flat a glass unless they tear it up. You do a very good job laying you liner. I’m impressed, but not everyone is that good. Hence the reason why it is in code.
If preslope doesn't at the very minimum aid in drainage of the water that reaches the pan, explain all the showers I've had to rip out that had no preslope and we're absolutely full of standing water? Not too say that a hack couldn't screw up a preslope style pan system. I for the record have never remove a leaking shower with a preslope. When using mud i do preslope unless I'm waterproofing from the top.
The water in water out system is going away like the phone booth, Nobody Does that anymore, topical membrane or some other waterproofing on the pan surface makes the pre-slope notion a moot issue
It's called condensation. It does get damp but since the area below is dryer the subfloor moisture can wick to the dryer area. But this is definitely not good for OSB or plywood over time.
Maybe fine for a small shower but my 9foot long shower with level floor and no preslope- on far end of shower drain that water would NEVER make it to that drain without a preslope helping that saturated pan direct water down.
I love the attitude, but I am a fan of 2 type of concrete, cracked and about to crack, then what ? I think you should slope the pan, but I would not know, mine has not failed. I think if you step on a sponge water leaves the sponge and finds its way out via gravity. Does it stand or flow ? My sponge is still wet but not like it was. What about vapor, ever see a fogged mirror that can happen inside your walls. To ignore these other cases of water penetration leads to failure eventually. What about changes in air pressure that will move water in your pan. But if you step on your pan you are pushing water out of the shower bed, even if its just the tile mortar. you could make an argument that too much water proofing is bad because you trap water when the polymer coated mortar bed fails. These details are the only difference in how long a shower lasts. Water does wick, but its not the only consideration. As far as I can tell, clogged weep holes is a much bigger issue. I had a shower that lasted over 30 years, no backer board at all, no water proofing polymers just diamond lath, mortar and a vinyl liner. No cracks no leaks. I think we get into the big box mentality and buy the new and shiny materials, when inexpensive basic materials will do the job just fine( at least for what you cant see). That is just one reason why I like StarTile videos.
What protects the water getting through 2in of mortar at the perimeter? Nothing, so then why would you need protection at the weep holes? Anyway it's a moot issue since we all waterproof the pan surface now, therefore pan will never see any moisture to begin with
You are forcing the capillary action by saturating the entire bed. Do this test with 1 gallon poured here and there, and see what happens. i would be impressed and surprised if it works the same way. Also,, this assumes a flat and level subfloor. Interesting video. We do a pre-slope, apply surface waterproofing then tile. Perfect for linear drains. Why be stuck with a center drain and small tiles? A single pitch allows any design one desires.
*Feel free to discuss amongst yourselves..Issac's video was flawed since he used a mat below mortar bed which gave a false result..., I have stated my opinion on this subject many more times than I care to, I have done a demo and stated my opinion again on all the aspects of a pre slope, it's a dead horse now and I won't entertain any questions or debate the subject here*
Well, what you DONT do, is apply caulk while screwing the cap on in between, which is what I did. Ow I can’t sleep thinking that there’s a shower I built, just waiting to fail.
It's all in the book preslope is always required
Laces out
I love tile drama lol! All of you main guys putting out videos are awesome! I applaud you all. Being a contractor myself I don’t have the nerve to do videos so my hat is off to y’all!
I love this guy he speaks alot of trash then ends up backing it up unlike 99.99% of tile guys keep it up 👍🏼 your the best !
I've been studying all you guys for several years; you, Diblasi, Ostrum, and others.
I base my common sense off of the calculations of all of your condensed wisdom.
I choose to do a preslope. I don't seal the final pan top until after I've done the water test to ensure the membrane is working properly.(when you do your water test, you're gonna saturate your pan no matter what. The water is going to seep up through your drain barrel threads and weeps holes.)
So after the membrane test passes, and I let it dry out for a couple days, that's when I will liquid membrane the top to seal it for the tile setting.
Sure, a drain can back up and still flood your drypack,but generally speaking, all water should egress out and not backup past the p-trap.
This is the process I've come to use as my ritual.
I appreciate all the videos all of you make for teaching us what does and doesn't work.
Keep the Info flowing!
Very interesting! Years ago and still in my country we didn't had shower pan liner or preslope. We used construction plastic whether it black or clear and for all them Years our showers never failed! I lived in my house for 38 years on a no slope shower made with construction plastic and never go a water problem! Thanks for reiterating the old days!
Why is your country not named ??? is it classified Top Secret ? Is it because no one has asked ?? Ok, What Country did you for 38 years only use construction plastic, either black or clear. I think that the plastic is from Alien Space time.
please send a photo of this amazing plastic sheeting , thanx.
Interesting experiment. Thanks. Most amazing part was the amount of work done inside the house. I kept expecting to hear a wife coming in the room and screaming "what are you doing in my dining room?" or something to that effect.
Thanks for your videos. After many tiling videos, yours always prove to be the most informative. You give peace of mind in areas where I feel I might have made a mistake.
As a long time handyman, I just did my 3rd shower pan in 15 years. On the latest, Worried about my pre slope being enough. just put to rest.
You’re the reason I tried without a preslope. The logic was there. I worked with an environmental engineering company for years and knowing how chemicals travel underground through soil and other natural (and unnatural) channels the preslope argument made sense- how could it matter if the water moved through capillary action?!? So watching this was awesome and I appreciate these videos.
I agree that the issue is not that the dry pack itself clogs the weep holes. However, isn't it possible that over time, with the addition of detergent residue, mineral deposits and perhaps mold, the mortar (in the weep holes) eventually becomes less permeable or impermeable?
I loved seeing this to show the silliness of pebbles. It makes the permeability of mortar bed perfectly clear!
Whether you pre-slope or not the mortar is not ever going to dry out in a shower that is in daily use. With the tile cap, water will not evaporate beyond what is held by capillary action. With tile on top and water just seeping through the grout, there will never be enough water flowing through it to wash out bacteria or mold.
So then, how do we prevent this from happening? Redgard the top of the mortar pan?
@@goskidmark I would. Either that or you could also use one of the other products like the kerdi or something.
But you can red guard the dry pack ! 😉👍🏼
Mold will not grow on mortar. Nor will it grow anaerobically.
Get a preformed pan. End if story.
I have been a flooring professional for 30 years. You my friend are a critical thinker and what you are explaining makes absolute sense. The question now is " how saturated do you want the mortar bed to be"? You have my attention.
Wet is wet...capillary action insures all pans ( water in water out system ) will always remain wet in void of air to dry out.
Going forward we all waterproof the the surface now, be it liquid topical membrane or a fleeced/clothe...
Keeps any moisture out so the pan is only for a slope at surface.
@@StarrTile Im pretty convinced that keeping moisture out of the mortar bed is the answer. water needs to go directly to the drain without absorbing into surfaces period. Water needs to escape before it can gather or absorb.
@@gwynja3191 Glad someone mentioned this. I was going to suggest that Isaac, mentioned in the video, uses a membrane over the drypacked pan (please correct me if I am wrong). Wouldn't this be the best practice.? This video is very eye opening and appreciated!
@JoeySchalger @G Wyneja3
someone posted this in the comments, since you missed the entire point of his demonstration.
"Everyone agrees that preslope helps. what he is trying to show you is that water will pull itself out of the drypack and into the drain without preslope. Preslope is only a requiment when you are on a concrete basement floor and the floor slopes away from the drain. In this scenario in his video, the base is perfectly flat and then the liner goes up the sides so it's like a preslope of 0 which in theory will drain. But when you have the slope of the base going away from the drain now you are relying more and more on the wicking effect to pull the water up the slope and over the hump. there comes a point then the water isn't strong enough to wick itself dry because your base is sloped so bad. SO if your base is flat this video proves it drains"
Preslopes make me feel good, plus they help me in defending myself when I get sued.
@Matt The Builder. Exactly, that's the point I was trying to make.
If your shower doesn't fail, will you still get sued?
@@johnnybear111 if your shower isnt pre sloped, is it gonna fail?
We waterproof entire shower now, making the pre slope a moot issue
It is actually mandated by Florida Building Code to pre-pitch your shower pan before installing a pan liner now...at least in my County
yes I work in alachua county fl, and pre slope is required
You and Issac both have great content. I have been learning a lot from you guys and now feel like I can tackle my own shower pan. I hope one day you guys will be able to come together and collaborate because I think it would benefit all of your guys subscribers. Great stuff.
Perhaps there really is more than one way to skin a cat???
I watched both videos and still cannot make up my mind. Inconclusive.
Someone mentioned in Tile Coach's video about making/using boxes made out of plexiglass. That would be definitive. To see in real-time how the water is moving and traveling. . . Gold!
In this video we never quite know how much water is sitting at the bottom from the pre-soak. In the Tile coaches video he used some cover at the bottom...
They will never collaborate because Isaac does it right and this guy does not.
@@johnsnetsinger7105 Depends on your definition of what *collaborate* means in YOUR head. Both Bob and Issac had a joint live stream event together so you can decide for yourself. Additionally, people can change their minds on certain products or techniques as more information and data becomes available. For example, the Earth was once considered *Center of Universe* and that everything circled around the Earth to appease the Roman Catholic Church and later Galileo (Italian astronomer) correctly asserted that our Earth circled around the Sun and was persecuted for it. Even Issac has now essentially stopped using the Schluter drains (both circular and the linear drain) since they have had many failures and since switched to preferring the Fx Flow drain which seems to be much better performing drain. Lastly, even Issac has said there is enough room in TH-cam to have lots of tiler slingers on the platform and it is not a contest where it is either Issac or Bob.
Everyone just convert to topical membranes and move on. I started off doing preslopes then went topical. Won't go back.
I know this vid is 2 years old, but it reminded me of an experiment back in middle school. If you take a stalk of celery and put it in food-colored water, the stalk will suck up the liquid far above the lowest point of the container. It’s an easier visualization of capillary action. So no, water doesn’t always go to the lowest place.
Slope or no slope. That is the question. I've watched both videos. Both to me look fine. But if I was to err on the side of caution, I would put in a preslope. Just for peace of mind.
The thing I see, is the pre-slope (just like the no slope) requires 100% saturation to work. Both you and Issac showed that. But if just one cup of water was put in at random all around, how much would leak back out? Putting on a layer of tile with the correct grout (by a professional, not an amateur like me) means almost no water will get in. Yes grout is porous, but done right it would only be "dampness" that SLOWLY gets through. All the shower water will run over the surface and down the drain. Like you said in your 2014 video, for the water to be able to actually run down a slope while covered in mortar/dry-pack it would have to be absolutely saturated and if THAT much water is under the tiles, then something is badly wrong and the entire shower floor will need to be torn up because grout and thinset will start crumbling.
i think thats the point hes making the shower has to be replaced eitherway if your having this problem so why do the preslope
Every shower I tear out with no preslope, smells terrible, which is caused by bacteria, this is my main complaint. At end of day, if water isn't leaving the pan and destroying everything, you are good(ish)
I agree with you and have watched a lot of you videos thank you for all the great info. You helped me so much building my first ever shower
wow Ive always done a pre-slope but I think Im convinced, I will definitely try to avoid doing them. Water always finds a way I guess. still its the Gravity pulling water down creating a drier area near weep holes and that drives the capillary action .
You answered your own question. Absence of any additional water...the bed will dry towards the drain/weeping system...via capillary action.
I posted this over at Isaac Ostrum video comments and curious what your thoughts are?
A Case for Non-pre slope
Just being the devils advocate here. First off I always put a pre-slope in my work due to avoiding any future liability but I don't think it's as important as we make it out to be. We need to keep in mind that the porous deck mud acts like a huge monolithic coarse sponge. Any monolithic material composition with particle sizes below 0.100" or less than 1/8" will have capillary action and will hold a "perched water table" at a certain level. I don't know what that level would be for deck mud(would be a great experiment as well) but it's there even if i't a 1/4". In a gardening container pot with the average potting mix you could have a perched water table as high as 3". An example may help. If you soak a long sponge in a bucket then hold it vertically letting the excess freely drain out and let stand for a while you will notice that the top is quite moist but if you squeeze the bottom then water pours out. That's the perched water table. Even with no pre-slope there is never any "standing water". I have never found much "standing water" in these demos. There may be some free water but it's mostly due to large cracks losing it's monolithic structure and or a large negative slope but not directly due to no pre-slope on a flat floor. Any water higher than the PWT is drained out of the weep holes. Moisture above the PWT is held tightly to the particles by capillary adhesive forces.
I appreciate your insight at explanation.. Perhaps others will benefit by it.
It is interesting to me that you are the fourth person to comment that you do a pre slope in order to avoid liability, I have yet to pull out a saturated smelly shower, or even one that had cracked from the constant water presence that was less than 5 or 10 years old, most have been in excess of 20 years plus that were Builders grade and many of the things were done incorrect. If I ever thought that not having a pre slope would lead to a failure in a year or two then I would definitely be on board to do them, it is just not the case
@@StarrTile 'perched water table' is the correct description.
Thanks for the experiment. Since you saturated the pan before the final test, all of the water came out since by definition, a 'saturated' pan cannot hold any more water. What we don't know is how much water did it take to saturate a flat pan vs a pre-sloped pan. And as Isaac says, is there a puddle in a corner that might have held less water if there was a pre-slope. And maybe a pre-sloped pan would drain in less than the 12 min it took for yours to drain. Just continuing the discussion. By the way, there is gravity all through the pan and the mud; it's just that capillary action can overcome the gravity for a portion of the water.
Came here to say this
@@user-xt1vs2oz3b Yes I agree. If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo.
I have built many pre slopes using 22/32 plywood cut to fit over the shower sub floor. A 3/4 riser at the outside and 2” drywall screws around the hole cut to clear the drain will provide an almost perfect slope to the drain. Good demo, thanks man!
I like your way of affecting a pre slope without mortar, sounds logical to me👍
I have seen guys do it with ¼ cement board, blocked up at the outer edge, and screwed into the floor at the center, with thinset to the up the slope under it.. the screwed once that's set.
I'm not brave enough to try it, but it's clever, if nothing else
I do not use pebbles and use the plastic disk too. So I agree on the point. Although the issue with no preslope is to help water from pooling in the corners of the pan or the low spots. This video shows those low spots. Now the issue is mildew growth. I have seen it on ALL non-presloped pans. All the corners will have mildew growth from under the tile and can never be removed. All of the presloped pans do not have this issue.
Sure not using a preslope is easy, drains 90% of the water, but mildew growth in the grout lines is a major issue with this.
This video is a prefect example of water pooling in the pan. All the water would have drained if there was a preslope going all the way to the drain. The mistake is Starr just props up the edge of the pan not the whole pan.
May Take 12 minutes without slope maybe with slope take 6 minutes byw u are a great tile master I like see a nice work done bcz i know isn't easy task to complete without years and years on real work field I know what's I talking about bcz I'm a plumber after 25 years I still learning from other trademan 👍
This is awesome! Thank God I don't have to do a preslope...
I still believe the preslope will allow more water to find its way out , however i am going to waterproof my shower beds to reduce the amount of water that makes it into the shower base, and hopefully reduce mold build up under the floor tile
When I did my first shower I did a pre slop mainly because I did not counter sink my drain like you do. So since I had to bring the floor up to the drain I did it. Like you say it couldn't hurt. But I also believe it is not necessary . Especially if the liner is installed correctly. Keep up the good work.
Do it right. If you don't want a stinky shower a few months down the road, do the pre-slope!
Everyone waterproofs their shower nowadays, including the pan surface....so no water gets into pan, so preslope for what reason exactly ??? 😂
Gotta think about things rationally
OK guys. First I'm not a tiler, remodel expert, builder. I am however a stickler for doing things right regardless what anyone wants to do. In my opinion both of you are right. I've watched both of you do your thing and you both seem very competent and skilled. I like watching Bob, no offense Eric. Bob states he is in this video thing to help people like me figure out what to do and what not to do. He takes time in his videos to explain (sometimes twice or more) what he did and why he did it that way. Makes perfect sense to me. He works alone running his own business and I expect being in Atlanta has more work than he wants, perhaps not. Regardless if where you live and work requires a permit and strict adherence to building codes then you do what you have to do. If you are reputable and do good work, back up your work with your reputation then you should never have a situation where the client is "out to get you". Now some might say that those building and zoning people don't know crap. Well, they are the customers best hope of making sure his job gets done according to some else's guidelines and requirements thereby keeping professionals or semi professionals honest. In Georgia, where Bob and I both reside, there are way too many folks out there running around claiming to be something they're not. Which makes finding a pro somewhat difficult because ultimately the customer really doesn't want to pay anymore than a fair price for quality work and materials. Eric, You run your own business with employees, that means you not only have keep track of what you are doing but what they are doing as well. I'm not advocating that your folks are not trustworthy or skilled in what they do, but I do know first hand that "when the cats away, the mice will play". I've learned alot in my sixty nine years on this planet and I am proud to say alot of it was because I pay attention to detail, after all the beauty of any job done right is all in the details, Bob pays alot of attention to details and makes that clear in his videos. I have a small project I am considering right now, I know how to get started, but if things go badly or not I am working with obsolete no longer made tile. So I may call you Bob. Good luck to you both, I just had to chime in. It's my opinion and I'm sticking to it.
Awesome. I wanna do a tile shower was just going to get an acrylic pan because a pre slope was too intimidating. Thanks for the info brudda
I appreciate the effort as much as anyone else but people should realize neither of these tests actually prove anything. Doing science is hard. One of the most important parts is having peers poke holes in your methodology. Here we have one test essentially testing the vaiability of a funnel. A plastic funnel with mud on top. Of coarse it works and you'll get all your water back. But that's not what your testing. Your testing whether its necessary over a non sloping funnel with mud on top. To that end it tells you nothing.
On the other hand you have the non slope plastic funnel. That was saturated before hand. Look, its not exactly a huge leap to realize that there is no other possible way for this to end then to get every ounce of water back. That is what saturating is. 100% of the space that could be filled by water..... is filled by water. Where else could it go? You could've built big pools under the mud and you'd get the same result. You've already filled the mud and dead spaces with water (the fact that there probably wasnt any low dead spaces is irrelevent. If there was they would've been filled little pools with the same end result.) Neither addresses the actual issues. Im not trying to be a pro skeptic here but the issue is a lot more nuanced and difficult then this.
As much as I loved mythbusters their methodology had the same issues. It wasnt science. It was just science influenced experiments. You could literally spend 4 years majoring in the ways experiments can be conceptually flawed. Researchers still get disgraced to this day by having their methods shown to be subject to basic biases.
I agree with this statement :) in the end there maybe a small influence of slope (gravity) if there are pools (gaps) in the stratum but its likely quite small. Since the influence of slope would be to increase the speed of the capillary action and time is not part of the experiment in a meaningful way... I am not a professional, so feel free to ignore my comments. I am a DIY, with my own bathroom remodel :) My take away is - slope the pan to assure efficient draining, redguard the pan to reduce influx to the pan, choose/maintain low permeating wall board, tile and grout.
If a serious amount of water is getting to your mortar won’t it just absorb it and slowly weep it out regardless of whether it is pre-sloped or not? Unless a small amount of saturation in the bottom of it somehow damages the drypack it seems the pre-slope is more of a precaution against a poorly or improperly installed pan-liner making it pointless if it was installed correctly in the first place. Just my two cents.
The only real advantage to having a pre slope is if your subfloor is off-kilter and you don't Rectify that before the pan material, then a pre slope would benefit you
Epoxy grout with a non porous material such as porcelain
Little did I know there was so much drama in the tile world
If you had a low spot in the pre-slope ( or no slope ) it could have been 100% saturated in those low areas. I think it's over saturation that breaks down the deck mud. The deck mud turning to sand is from it being over saturated for an extended period from clogged weep holes. So those low spots with no pre-slope will turn to sand before long, it's not from shampoo.
The pea-gravel is for long term use, it will work sort term without it. Those two dozen small holes with just deck mud around them would soon get clogged from deposits. The gravel greatly expands the area taking longer to get clogged.
I think the issue is also the fact that by the time you are relying on preslope to drain a saturated pan you have a significantly bigger problem on your hands and a failing shower. Preslope or not it's failing.
And how is that? Before liquid water proofing there was nothing standing in between. I can tell u rite now 99 percent of showers leak right threw the grout into the pan. And have been functioning like that for years upon years without the floor caving in or whatever you think might happen
I suggest we do comparison experiments for saturated pan with/without pre-slope to see if there is a difference in the amount of new water that replaces old water. First let's use water with certain concentration of ink to saturate both shower pan mud beds, then use clean water to 'wash' the mud beds to see if there is a difference in the color of water coming out of both mud beds...
That's a great idea and an experiment like that would be the only way to truly know if water is cycling.
Having said that it's a moot issue because everyone waterproof their pan surface now so no water gets in to begin with
@@StarrTile
What do people use to waterproof their pan surface? Redgard?
Yes, or Aqua defense or Hydro ban or 8 + 9 or Kerdi
This was a awesome. This shows dont reguard the shower floor it stop water going into the weep holes
If water gets into your mortar bed which is mortar then how is it that it cannot get into your clogged weep holes that are clogged with mortar, irrational 😂
Great video Bob, the demonstration was very interesting and well explained.
A pebble would have to be a perfect sphere for it to clog a weep hole. Also dont use pebble that are small enough to get stuck in a weep hole.
TileCoach > StarrTile
Just a word out there for all the Tiny House [on wheels] DIY builders -Pre slope the shower, because you KNOW the trailer supports are going to sink 😉
Great video! I like how all your videos are thinking videos. Details matter for sure & the solid pebbles blocking weep holes makes sense.
Both ways are fine if your plywood is level or you seal the deckmud top with redguard or a waterproof membrane. If its not then you could have a small pool of water sitting in the pan low point which is why the code required the pre-slope under the PVC.
Why not do a pre-slope??
I don't understand why it's even a debate?? The cost and labor of doing a pre-slope, is nothing compared to the cost of the entire job. Please, if you ever do my house, do a pre-slope. I'll pay the extra extra change.
Plus....
Assuming that's a 2' level, it's only an 1/8" per foot. When you add the second shim, then it's a 1/4" per foot.
You're trying to convince everybody, based off your opinion.
Why?
Mainly it's a moot issue nowadays because everybody is waterproofing the top of their pan material, a pre slope will be insignificant and irrelevant...
But as I mentioned in the video, your pan is 100% saturated whether or not there is a slope underneath or there is no slope, breaking down the binding components of the mortar. But again, a moot issue nowadays.
Don't know if I thinking cornetly... If I do preslope and than read guard on the top than slop... Than if Wather penetrate slope.. Stop on read guard and goes down cuz preslope... Right? His with out preslope Wather gonna stay somwhere in lower spot... Please explain
Thx
I waterproof the entire surface of the shower so no water will ever see the mortar mix, that's why I don't do a pre slope because it's irrelevant
Yes but Wather stay i nie low spot with out preslope right? And with the time... Gonna be bad smell there and moulding..
I never used a pre slupe before shower pan and no problem at all
I have had second thoughts about this matter. If a small leak was to happen in the bottom of the pan were the first water collected then that water would RUN OUT the leak and then that water would be topped up by the next shower, repeatably. With a preslope all water would run out and only a minor amount of water would be available to leak through. So if that is true then the matter to be faced is if anything goes wrong with the pan liner install then the potential damage below is minimised. With a flood test the water pressure above would push down on the pan liner minimising leak flow. the empty tile bed would not exert the same sealing pressure. So both tests work but the long term out come from the failure of a less skilled installer may be minimised by the preslope. I am about to do a second bathroom, the first i did years ago without any water proofing on a ground slab with a slope to the outside. I 'lucked out', no damage inside. I just followed the old trady's advise at the time. This time upstairs no mistakes.
Removed a 30-yr old shower in FL. No pre-slope and no sitting water on the liner. No water-proofing of the mortar bed top either. The drain base was resting on top of the subfloor, 1/8" above it. That's a data point supporting his claim.
"Do the Experiment". The surest way to accurate knowledge.
Flat earther's: Yeah what he said, does a marble roll when you put it on the earth? Lol
What I do, is that once my drain is set I will use scrap pieces of 1/2 cement board and install it in the shower floor around the drain. Than mix some sand mix and do a small pre slope. Just so that I have a pitch towards the drain. I try to avoid having a big shower floor. The big step up will be a negative on my customers. What are your thoughts?
Does the mortar adhere to the rubber underlayment like glue after it dries? Or after the mortar dries and shrinks a little, would it be possible for some space or gaps to occur which then the pre slope would always be aiming that residual water back into the drain?
Although I would like to answer your question we are all doing a sealed system which now makes a pre Slope a non issue and antiquated
Hi this is nice testing but it is not in real life testing. First you supposed to build the regular size shower not 3 by 3 feet shower. If is smaller water can penetrate much faster and easier because the distance to the drain is shorter.
I think it is depends where you have the drain. If you have linear drain 4 inch from the wall you probably need to do that pre slope because water can set across the drain wall if you don’t have the pre slope. This is very good question you need to have it pre slope or not.
So you measure a 1/4in at the end of a 2ft level and call that correct. You just said there should be 1/4in slope per 1ft length. So should you not have 1/2in at the end of the level.
1/4 per foot, one foot is one side of the pan
I will do preslope in my own shower
I learned to mortar the shower with slope without the clamping collar on . Then install a shower pan. Then idk what the tile guy does after that. Which makes sense, like a water slide to the drain.
It’s not just capillary action, it’s hydronic pressure, the pre slope is just for incase but with that said, water won’t wick to the pan just because. Experiment is flawed. It’s not the end all of you don’t preslope but over time you can end up having an issue a extra 30 minutes can 100% prevent. The mortar bed is porous and if it is to get completely saturated and make it to the rubber liner then there’s a good chance it’s not goi g to come all the way back up thru it or wick it’s way to the drain
I think the first water in goes to the bottom of the motor bed and stays there forever. new water, coming from next wetting events, never mixes with the first water, it simply goes down to the the permanent bottom water and that new water flows off, out the weep holes. It does not ever mix with the first water. In fact in the ocean, water layers can remain permanently separate. Military submarines hide under these layers of water, but i digress. In fact soils hold water for years. In Australia, old roads, 20 years old or older, they have dug up have soil moisture exactly the same as the day the were built. even in very dry areas with drought being a regular thing and very low water tables. Great demonstration. intuition can be misleading.
I've been doing residential demolition/renovating for 8 years now, every single bathroom I've ever taken apart has had water saturated in the pan liner. I have never seen anybody do a sloped pan before the liner except on youtube.. It makes way more sense though if the liner is not sloped how does water drain out properly.. I watched your experiment but with daily use you are going to have alot of water sitting there and it will not dry up as fast if there is tile and grout on top.. Sloped pan will be more hygienic as you have fresh water being introduced and shed constantly
Wonderful work bro!
My only argument is that the measured water that you added just displaced the water that was already in the pan. The excess just ran out the bottom, plus the newly displaced water, which is why it is equal to what went in before hand. However, the water in the bucket after the experiment is not the same as the water that came out of the bucket pre experiment, not all of it, granted there is no way to tell how much of it is the experiment water, or presoak water. The only way in my mind to truly test this would be to weigh the mortar mix before adding water and then again after you soak it, to determine how much water this thing is actually holding. If you were to take the pan out of the pan liner you would see that there is water left in the bottom of the pan liner. There has to be... granted this might not happen on a preslope, but either way I don't think it would be enough water to matter. Just my thoughts on the experiment.
I totally agree with this comment. 30 year GC here and I don’t understand why you are so stuck on proving a preslope doesn’t work. I found your scientific experiment flawed. The very fact that you didn’t measure the water from your very first pour to saturate the pan tells me that water could have been sitting in the pan as this commenter pointed out.
If you don't waterproof your pan surface, which by the way everybody does now so it's a moot issue, then you're always going to have a water content in your pan, a my experiment I was replicating that water content, if I had started out with a dry pan then obviously the same amount of water coming out would not measure up to what went in.
But to the bigger question that you propose, why am I intent on disproving a pre slope functions as intended? Well you just kind of answered your own question I am proving that it does not function as intended, people are brainwashed into believing that it works, in the void of gravity then capillary action kicks in making it impossible to function as intended... it would only work if there was no mortar, like drain lines do. I know it's a little bit like finding out the Santa Claus isn't real but a lot of people still believe in things that aren't true
@@StarrTile I think that you prove the point supporting pre-slope when you added the half-inch shims. The water that was stagnant on your pan lining was displaced when the shims were installed. (Simulating pre-slope)
@@kaboom362 only at double the 1/4 inch per foot which no on does.
I don't understand why anybody would believe what Isaac has to say anyway, he has eight or nine videos of his failures..
and just like you said he cheated on his experiment so has zero credibility
Yes indeed he has quite a few failures...coaching is a tuff gig 😉
to my understanding, you said the soapy shower water deteriorates the sand-mortar mix. It deteriorates the cement components and leaves the sand behind. So anytime water gets into the mortar mix is bad? Is this correct? or is it ok for the mortar mix to get saturated? I realize that you use thin set around drain and you mention it helps the redguard waterproofing to adhere better. that was said in another video of yours. then you coat with redguard. This is to ensure that water never actually enters the mortar bed but it is there as a backup? This is my understanding of the video, am i understanding correctly? This is very helpful to me.
The backup is the pan liner. If installed correctly, it should also stop water getting into the mud bed.
awesome video.... so I saw a video of you applying Red Guard... is this where I would apply it ? onto the mortar ?and then after 3 layers.... next is thinset for tiles ?
Yes
@@StarrTile would also like to ask you about the type of grout to use on floor tile in the shower floor. should we be using epoxy grout or something else ? TIA
I use Prism by default on every job I do the last few years
Can I ask, the major thing I see different between you and other shower guys is you waterproof UNDER the mortar bed. Many others do the bed right on the slab or plywood subfloor, and then they waterproof overtop with membrane or whatnot and many of them NOW (after I presume watching you) they almost all apply a waterproofing like redguard or it's equivalents ontop of that. If the redguard or whatever is the end all why do the waterproofing under the bed? I've even seen you use membrane instead of a liner on tricky showers before your mortar bed. I'd like to see that test, do you need to waterproof under your mortar bed. I suppose in the end if all else fails it's one final redundancy but you tend to shy away from that besides this.
The shower pan liner be it CPE or PVC will not last forever if water is sitting on it. Just like everything else overtime it will deteriorate and eventually fail.
However for every shower pan liner you put in without a pre slope it will fail in probably 200 years. With a pre sloped the shower pan liner will fail and 350 years. In other words, you will be long dead, as well as the original owners, and there will be nobody to sue when the pan liner fails, and pull more importantly when the building is resold with the warranty as is.
With the building industry today, buildings don't last that long and neither do bathroom since they are remodeled every 15 years and rarely will a bathroom make it 30 years.
This is why in my state of Michigan they eliminated the pre slope in the building codes because it is just an extra expense that's a needless to the homeowner.
Jeff D
Living in a condo complex on the second floor?,
I demoed a 60 year-old shower because I was afraid the shower pan had failed.
No cracks in the tile, leaks onto the downstairs neighbor, or anything like that just OCD fear of liability claim.
Absolutely nothing was wrong with it. Even the membrane was in pristine shape!.
Chicken-wire tile too by the way....uuuughhhhhh!.
Okay, most interesting demonstration but the comment at the end is most relevant to me: "most tilers are...waterproofing their pan surface". That's what I'm struggling with. Someone please explain why anyone would build a shower pan out of a porous, unsealed material. You wouldn't install a toilet or a sink that's porous to water.
Bob why do you redguard your whole sand and cement bed in other videos if your no preslope is the way to go. Looks like the weight of the sand and cement made the center lower somewhat giving you a preslope
I started waterproofing the entirety of my for a couple of years ago, that's why the whole notion of a pre slope is a moot issue, but Isaac had challenged me after he did his video so I took him up on it
@@StarrTile Exactly. This is a non issue if you just waterproof the mud bed. Common sense solution when the issue is getting water into the mud bed.
In Memphis a preslope is code. There is a shower pan inspection prior to being able to start a shower that checks for proper preslope & pan installation. It’s code! That’s all you need to know bottom line. “If all else fails read the directions”(Preslope is part of the directions for shower pan installation). And lastly, what’s the number one rule of plumbing...Water rolls down hill😂.....BTW, 30+ years of being a tile contractor in the Memphis area.
Water only rolls down hill in a gravity induced environment , that quarter inch per foot is a plumbing code for sewage pipes, it doesn't work that way with a 150 lb of mortar capillary action will take effect... your pan is saturated with or without a pre slope. But the whole notion is a moot issue anyway since most people are waterproofing the surface of their pan
@@StarrTile yep well said Bob.
Too me, it seems like there is no disadvantage of a pre slope besides dry time. Use a lot of pebbles and dry pack so it doesn't mix.
Which is 100% irrelevant now since everybody is doing a sealed system....
The pre-slope has gone with the phone booth 💯
seems to me "capillary might be better than gravity" BUT "capillary PLUS gravity" might be even better ..... I suppose no slope is not a critical flaw , they've been done like that forever , but maybe a little slope is just a little added extra benefit , not critical , but just a bit better , can't hurt .... That's my take on it
Interesting video. But wouldn’t having no slope at all cause some water to pool on the shower floor without any way of being evacuated other than through evaporation?
Wicking action would ensure that your pan would be wet all the time, the fact that there is no gravity because you're dealing with a mortar bed that gets saturated would not allow water necessarily to pull anywhere, all that being said it's irrelevant now because we waterproof the surface and thereby the mortar never gets wet
@@StarrTile thanks for the reply. But I see from your other videos you slope the tiles towards the drain (your golf ball demonstration).
Bob, here's something that occurred to me re the experiment--whatever water there was that wouldn't drain from the pre soaking, would cause any additional water to exit---because the space for static water's already taken up. I wonder if a better test might be to do it by weighing. As you said a little water will remain and that, I think, is the problem---it would never drain dry-- it' would always just sit there (though it would be replaced by the new water, of course)---do you see what I'm saying on this? It would never be dry and I'm thinking it would foment mold more quickly than with a presloped pan. What do you think?
You are correct, there would always be one hundred percent saturation, but the theory of new water taking its place is flawed, all the water doesn't know to evacuate when new water comes in, plus the new water is Tainted by the person being in the shower, the theory is that the old water has chemicals, shampoos and soaps and body scum, the new water is supposed to take its place but yet you have the same material going in that are going out.... the only way the water in water out Theory would work is if the person was never in the shower
What if you saturated the pan with clear regular water and the dyed a separate bucket with a color and see if indeed the water isn't replaced when it drains down to be recollected? . 🤔
S9...I am installing or cutting into a cement floor to have the shower tile sloped into a floor drain. Can I just place a strip of pan liner around the edges up on my 2x6 backers and extend down into the pan not putting the pan liner all the way down to the drain? Of course I will be putting thin set to smooth out the cement to put the tile on. Thanks for any input
I’m thinking that the weight of the mortar bed on the wood floor will make the wood form to the slope of the mortar bed.
Newbie question alert!: If the mortar is porous and eventually deteriorates,why not just use concrete in the first place?
It will only deteriorate if you don't do it right or waterproof it, you cannot use concrete because it has rocks in it and you could never get it flat and level, even if you could it would be problematic
SO MR STARR. are you now using redguard over the entire dry pack? i know at one time you were just doing like 6 inches around perimeter. what i dont get is the words " mold sandwich" i see this phrase every time someone asks can you use a liquid membrane over a water in water out system, well why isnt this mold sammy happening in a schluter type system? i guess the only difference would be that in a schluter system the water under tile is making its way to the drain but afaik thats not happening as the water just evaporates, but if it did then just dont put liquid membrane in the general vacinity of the drain in a liner system and that water would also drop down to weep holes...
After your pan is 100% saturated water will ALWAYS find the lowest point. Having a preslope ensures the lowest point is the drain.
It hasn't been proven since wicking action will insure pan is saturated all the time...
That being said it is irrelevant now because we are all waterproofing the pan surface so now the mortar will ever see any moisture
Would an alternative pan method be sloped mortar base(no membrane) with a recessed non weep hole drain, coated with two or more coats of Red Guard with the coating continuing up the walls. Would this be the same as Custom Products preformed foam shower bases with Red Guard (but much more inexpensive)? Would the sealed mortar base trap moisture between the tile and the base, and create smelly mold and mildew? For a shower used daily, is mold and mildew an issue regardless of the pan system used? I wonder if a daily used shower pan ever dries out during its lifetime? Finally, does all the controversy over shower floors make preformed acrylic and cast iron pans the ideal shower floor?
Great video...thanks for taking time to demonstrate capillary action of water!
I tear showers out all the time with no presolpes the all hold water...think what you want but they are needed.
Yes I do the same, I have a library with 350 videos and you will see me tearing out saturated shower pans all the time... but a lot of mistakes go into those pans when they are being built including not making sure the floor is level, just because there is a failure you cannot blame it on one thing alone, operator malfunction is prevalent 👍
@@StarrTile I can't understand why you are so anti presolpe? Just do it the correct way manufacturers have it in there instructions local codes call for it...give people the correct info.
@@Tilethoughts I'm against it because it hasn't been proven to be effective... I prefaced the video by saying that I never tell people not to do a pre slope, I just show them as I have here what happens without one and Isaac did one with one and we have the same result, sorry buddy I'm not a book Soldier I question things 👍
@@StarrTile how has it not been proven to work? Everything is sloped to the drain just like your finished shower floor...why not just do your finished floor level?
@@StarrTile if you so strongly believe that a level floor under your liner is sufficient please make your finished tile floor level as well same concept.it should drain just fine with your logic.
Man's right about pebbles - don't need em
Love your videos, so thanks for sharing your knowledge! Can you tell me if my thinking is right with this approach:
Using a Flo FX type drain without weep holes makes the pre slope totally irrelevant, , right? My approach is: 1) tar paper/plastic sheeting right over the plywood substrate; 2) staple metal lath; 3) build mortar shower pan with the right pitch with Flo FX installed; 4) install waterproof membrane like Kerdi or liquid waterproof barrier like Red Guard, Hydro Ban, etc. over the mortar pan; 5) install floor tile.
No need for the 40mil plastic liner in this case since the waterproofing is happening on the top of the pan, right?
Yes suppose your way would work... there are many many ways to do the right thing as long as it doesn't leak at the end, I don't necessarily agree with doing it for a customer because I don't want to toss people failure.
Having said that I waterproof the surface of my pan so it also makes the pre slope obsolete... and I don't need the flow drain for that
Hi, neat experiment. But I have a question. Did you seal the threads to make sure no water was escaping around that drain barrel? I didn't see or hear that mentioned. That could make a difference in the result.
Next, i see in comments people saying that "capillary action is stronger than gravity". This only applies if you DO NOT HAVE full saturation in a substrate. Its called wicking and is due to waters high surface tension that causes adhesion. Full saturation creates hydrostatic pressure. Hydrostaic pressure created by gravity will make the water flow to the lowest point always.
As the pan loses its full saturation state, and evaporation occurs at the surface, wicking kicks in again and will start to pull any remaining "puddles" of water from the bottom interface hence your result here.
Also think about how a finished concrete floor gives off moisture from below to the surface. Its the waters high surface tension and "wicking" action at play but not when in a full saturation state.
A pre-slope will certainly make a saturated pan drain a little faster, and I believe a pre-sloped pan would likely dry out a little faster than one thats not, but I think the difference would be negligible and not important to these applications.
I agree with the author on all his points. Pebbles gonna do more harm than good and if your pan gets saturated, pre-slope gives no real benefit.
Now my question is, since all tiled floors with grout joint are usually "sanded" grout, they will not stop water egress to the pan mortar. Sure you can seal them, but how long does that last? My question is if ALL tiled floors fail to keep water out of the pan, can the pan itself then become a "mold factory"? Now thats what I want to know.
How many pans have you demoed where you saw pan mortar failure (due to constant saturation) and also how many have been laden with mold?
I've demo'd enough of these types of showers to know if your putting a new shower in your house go with a newer waterproof system (wedi, schluter, ardex, prova) every single one ive ripped out has disgusting sitting water. Pre slope does make a difference they tend to at least not have standing water. Starrtile is crap ass set in his ways and that's fine but guaranteed his shower pans are bacteria breeding grounds
I am not a tiler, but a slope makes more logical sense than a flat surface for directing water once it gets to the bottom.
Now the debate perhaps should be how much pitch. Is it .25 inches per foot or .5" based on how much faster the water drained once you went from 1/4 inch to 1/2.
Again not a tiler but when you mention using common sense/logic, you were speaking my language. Lol
Anyway awesome video.
As a standard plumbing code a quarter inch slope per foot is great because you have air/gravity working on the water, in an encapsulated area as you have with a mortar bed gravity is proceeded by wicking action and therefore your pan will be moist all the time regardless of any type of slope... but yes, a quarter inch per foot is what they call for, having said that everybody waterproofs the pan surface now so the whole pre-slope notion is antiquated.
@StarrTile Thank you for responding so quickly. I have watched a few of your videos and will now watch a few more to understand better the differences between your preferred method and TileCoach's.
I am looking to redo my own 4x3 shower which currently is on plywood with fiberglass pan and surrounds...
Any specific videos you can point me to would be helpful.
Cheers.
@@PastorAngelV
th-cam.com/video/5Gp-PgGYi64/w-d-xo.html
@StarrTile Thank you Sir, appreciate you?
If you don't want any water getting into the bed then waterproof it before installing the tile. This whole issue is about water getting into the mud bed. If you waterproof the mud bed then a presloap is a waste of time, in my opinion. Plus you will not have the bed decay over time and mold inside the bed if water seeps through the grout.
Your 1/4 inch shim put a slope across the entire shower mockup; 18 to 24 inches; not the 9-12 inches to the drain. The 1/2 inch shims gave a 1/4 inch per foot slope to the drain, which gave you a better evacuation.
whats the big deal? seems to show it doesn,t matter either way. The mix used has barely seen any cement so not surprisingly crumbles sometimes and is very porous
I’m not arguing which is better, but in Florida a preslope is required by code. Also, a permit is required for the pan liner. That requires it to be installed by a licensed plumber. Just saying.
yes I understand what you are saying, however I have worked a dozen times in a Florida taking out shower and have never seen a pre slope, but then again there are certain States that require a boatload of things like California but yet jobs are still done wrong.
And when you waterproof the entire shower including the pan then the pre slope is a moot issue and would never kick in any way so it would be a waste of time
@@StarrTile i don’t disagree totally with your logic. However, the purpose of the preslope is not just for a the water to fall. It is also to overcome the unintentional wrinkles or air pockets that may occur during the liner install. If installed perfectly flat and wrinkle free (heating it up) then probably no problem. But one cannot say that their liner is 100% flat a glass unless they tear it up.
You do a very good job laying you liner. I’m impressed, but not everyone is that good. Hence the reason why it is in code.
Pre slope is before liner goes in
Yes
If preslope doesn't at the very minimum aid in drainage of the water that reaches the pan, explain all the showers I've had to rip out that had no preslope and we're absolutely full of standing water? Not too say that a hack couldn't screw up a preslope style pan system. I for the record have never remove a leaking shower with a preslope. When using mud i do preslope unless I'm waterproofing from the top.
You've just agreed with StarrTile's argument. He always waterproofs the mud bed. That's why he says a preslope is not necessary.
The preslope just makes sense to me. Your going to have that water stagnant in the low spots. It’s a water in water out system.
The water in water out system is going away like the phone booth, Nobody Does that anymore, topical membrane or some other waterproofing on the pan surface makes the pre-slope notion a moot issue
Thanks for the video Bob! I agree with your methods. I wish you were able to show the plywood underneath after the test. Just curious if it was damp.
Uncle Bud
He put the rubber shower pan before he put the mortar bed.
Why or how would the plywood underneath get damp?.
It's called condensation. It does get damp but since the area below is dryer the subfloor moisture can wick to the dryer area. But this is definitely not good for OSB or plywood over time.
Maybe fine for a small shower but my 9foot long shower with level floor and no preslope- on far end of shower drain that water would NEVER make it to that drain without a preslope helping that saturated pan direct water down.
Doesn't matter now. We do sealed systems so pre-slope is irrelevant🤦🏻♂️
If the floor is un level from the start pre slope seems to be a no brainer
Except that nobody does those anymore because we waterproof the surface of the pan so it is a move issue and absolutely irrelevant
I love the attitude, but I am a fan of 2 type of concrete, cracked and about to crack, then what ? I think you should slope the pan, but I would not know, mine has not failed. I think if you step on a sponge water leaves the sponge and finds its way out via gravity. Does it stand or flow ? My sponge is still wet but not like it was. What about vapor, ever see a fogged mirror that can happen inside your walls. To ignore these other cases of water penetration leads to failure eventually. What about changes in air pressure that will move water in your pan. But if you step on your pan you are pushing water out of the shower bed, even if its just the tile mortar. you could make an argument that too much water proofing is bad because you trap water when the polymer coated mortar bed fails. These details are the only difference in how long a shower lasts. Water does wick, but its not the only consideration. As far as I can tell, clogged weep holes is a much bigger issue. I had a shower that lasted over 30 years, no backer board at all, no water proofing polymers just diamond lath, mortar and a vinyl liner. No cracks no leaks. I think we get into the big box mentality and buy the new and shiny materials, when inexpensive basic materials will do the job just fine( at least for what you cant see). That is just one reason why I like StarTile videos.
So you have nothing protecting weep holes?
What protects the water getting through 2in of mortar at the perimeter? Nothing, so then why would you need protection at the weep holes?
Anyway it's a moot issue since we all waterproof the pan surface now, therefore pan will never see any moisture to begin with
You are forcing the capillary action by saturating the entire bed. Do this test with 1 gallon poured here and there, and see what happens. i would be impressed and surprised if it works the same way.
Also,, this assumes a flat and level subfloor. Interesting video. We do a pre-slope, apply surface waterproofing then tile. Perfect for linear drains. Why be stuck with a center drain and small tiles? A single pitch allows any design one desires.
So how does waterproof membrane like Redgard affect this test.
th-cam.com/video/qdpYnUU_owQ/w-d-xo.htmlsi=qFVo5UHgYZLyugLP
Solid Bob. Thanks.@@StarrTile
Stuff weep holes with bread water will dissolve