Waterproofing your shower, Do you really need it? Plus flood test.

so this shower was maybe five six years
old all marble and it started to leak okay so here are a couple of other
options for waterproofing I’ve got the ardex 8 plus 9 so this bathroom floor here is marble
got it all covered up and this is the jacuzzi I know I’ve got a lot of tools all over the place but there’s really no room to work in here and then this shower
here was all marble including the ceiling and the floor
and it leaked so it had to be torn out and now i’m redoing it okay so I got
this shower all prepped and ready to be flood tested like in the the bonding
flange there and I put some water in it last night before I left to test to make
sure that that plug is not leaking just a little bit so I can I can check it if
it was leaking then the flood test wouldn’t be it wouldn’t be
correct so now I’m gonna pour all water in here I’m gonna get up to a certain height and then I’m gonna go mark it and let
it sit for 24 hours and I’m gonna come back and check to see if the level has
changed and that’s how you do a flood test now I am certain that this isn’t gonna
leak because i’ve done so many of these and a flood tester pretty much every one
of them and never had a leak so why would you want a
flood test it well just to be a hundred percent certain that you didn’t do something
wrong that there’s no defect in the material and that when you cover it
with stone you know if there’s a leak it’s not from what you did
it is probably from gonna be from a pipe or something else or the drain or but
it’s not gonna be the tile installation so when you using a sheet membrane like
a kerdi membrane over durock or you could be using durock and then applying a liquid applied waterproofing membrane like mapei aquadefense hydroban laticrete hydro ban or some other or even ardex 8+9 they’re all good waterproofing materials there different me they’re all
liquid applied like the ardex you mix it and then you know it’s got two
components and you mix where’s the other one’s come to premix in a bucket they’re
all so good stuff but you have to install correctly the sheet membrane or the kerdi board is another
level above that because it’s actually a fabric this is a piece of kerdi band and
it’s actually a fabric of waterproofing sheet over the kerdi board this one here
is just turn the other way around that’s why there’s no gridlines so oh you could
put a durock up and then put a sheet membrane up so this is a sheet membrane over here do you buy a roll sheet membrane
which is which is actually on the floor here and I put kerdi band all in around
the floor and wall connection anything mud floor I show you picture that also okay so here are a couple of other
auctions for waterproofing I’ve got the X 8 + 9 this is 2 component really mix
then we’ve got a Hydra bin this is a liquid of by waterproofing membrane and
you look in the bucket and sorry all set to go you might have to just mix a
little bit but another sheet membrane here this is a ladder Creek ship
membrane and then another this is it comes in a longer well this is the noble
steel sheet membrane and then our X also has a has that has a sheet via membrane
and then there’s obviously the a aqua defense I don’t have a bucket of that
that right now but that’s a similar to this one here and you know there’s many
different options for waterproofing well the tile itself may be waterproof
depending on the tile the ceramic tile absorbs certain amount of water
porcelain tiles absorb much less water but that’s not the issue
Deas wall this is the wood wood construction this house is all made of
wood it’s got two by fours and on 16 inches the floors made this joist and
then this plywood will always be over it so it’s all wood and we’re know England
here this is this is the Boston max a little bit north of Boston here on
this job and we have fluctuations in temperature from could be in the home
the summer could be as high as 95 even 100 degrees in the winter it could be as
low as freezing below freezing right now it’s 18 degrees outside so it’s pretty
cold so there’s a lot of expansion and contraction going on around in the in
the house you might say well the house is climate control well its climate
control because it’s kept it at a temperature caused pretty constant
temperature in the summer they have a AC in the winter they have have heat so
it’s inside is pretty much constant temperature but outside the house is
subject to fluctuating temperatures and then the amount of humidity in the house
always changes as well in the winter it’s very dry in the summer it can be
very damp in just the amount of water that guys that penetrates into the lumba
can make it move quite a bit so what does that mean for the tile isolation
means that the tile on the walls is gonna be subjected to movement
especially in the corners were ever-changing point so as I was saying
the tile may be waterproof and for a new installation I like the bed the very
beginning when you install the tile and your grout it it may be completely
wonderful but that doesn’t last long because of all the pen all the woman in
the house it’s gonna it’s gonna it’s gonna move you’re gonna get micro
fissures you’re gonna get get movement and water will always get behind the
tile so when the water gets behind the tile that’s when it creates problems so
now if you have a waterproof shell completely waterproof what it gets
behind the tile is not gonna penetrate into the cavity wall you guys just gonna
remain in the shower now you might say well you know the show is only you
maybe two or three times a day could be to come be one it could be two three
times a day it’s you know this is a master bathroom so probably use at least
twice a day so how much what is it is that real well
think of the like the Amazon rainforest it gets I don’t know maybe a hundred
inches of rain a year I don’t know what that number is but that’s nothing
compared to what happens in a shower in the shower someone’s gonna take a 20
minute shower and depending on the the fixtures and the amount of water come
something you might have to three videos a minute for 15 minutes just imagine
that amount of water coming into this shower and washing on the walls and
soaking on the floor that’s a lot of water that you don’t want penetrating
into your substructure and come and creating problems with mold and rot you
need to have here it’s got one in the ceiling it’s got a rain head here and
then it’s got a body spray and then we got a knee wall and then we’ve got the
code over there that curb is never gonna see any water because there’s actually
not gonna be even even a glass door here it’s gonna be a glass panel over here in
this this area here from there to here that’s gonna be a glass panel and that’s
it so all the was gonna be contained over here this come back and then I
could start the tile so this shower was maybe five six years old all marble and
it’s time to leak and the problem was in this particular shower was in the drain
where it wasn’t properly attached I didn’t actually rip it out so I didn’t
see what the construction was but I did see that this month was all completely
wet so building quickly water flow sure you could take a shower in here right
now and I wouldn’t like so that’s why you want to do the waterproofing before
you install a tile so when water does get below the tile it’s not gonna okay so I got ten gallons in there right
now gonna add another so I’m gonna let that sit overnight and and we’ll see how it goes
see now it’s deeper yeah come over here because I bet this all slanted down right here
we’ll come back tomorrow make sure this is at the same level if it is u T so
this is 24 hours we see if I can reach what I’m
thinking about okay so the water is all drained I’m
gonna try it up a bit and start setting some tile


As a machinist I appreciate detail. I can do anything with the right instructions, and I'm about to re-do a bathroom. This guy is the best of the best and believe me I've looked.

A little off topic Sal but have to try and catch you when possible. Could you point me in the right direction on how to contine into the niche area of a shower wall on a herringbone? It's been quiet here in London over the last couple of weeks so knocked up a mock wall and had a play with the herringbone as don't normally do it. Pulled out the 90/45° lines and everything went fine untill the niche area. Couldn't get the grout lines to match on the internals. Any advice would be much appreciated👍

Man is a machine! Thanks for taking the time to do this and thanks for showing people how to work to eat. Hats off

Is this system ok for a steam shower if installed correctly or could it fail even if it was installed correctly
I know strange question, but I have seen to many fail that were “ installed correctly “
I have a project starting soon with one and as strange as it sound I’m a contractor who cares and takes pride in his projects

Great video Sal. Quick off topic question. What do you usually use for your niche shelves? Is tempered glass a good option?

I'm doing a remodel of my bathroom, going to get a new tub, only one in house, so I want to keep the tub.
For the tile area, going to take it back to 2×4's, then new 1/2" drywall, 1/4" cement board, 3 to 4 layers of Redgard, man made tile and grout with Mapei Ultracolor Plus FA.
Do you think this combo will work?

The kerdi seams aren't 100% waterproof. Thinset is porous and this system can fail. You're leaving room for failure. The kerdi system is a water management system. Paint those seams with hydroban so it's 100% waterproof.

I have used the schluter system for years. I have never done a water level test and I have never had a problem. I'm not saying it's not a good idea, but i'm so careful when I do one of these, I feel like if I came in and the water level had dropped, I wouldn't know where to begin. Maybe do as some say and add waterproofing to seams? I know it voids warranty, but they would find something wrong with installation anyway.

Plumbing code requires flood test to pass inspection in most states.
The test requires water to be filled up to rough curb.
Shouldn't we be following the code?

Hello Sal,your videos never fail with great content.I'm a licensed Contractor in the NY area.I have used Schulter Systems and Laticrete products faithfully with no issues.What issues I come across on failed Bathrooms are weak structure,plumbing and incorrect installation.May it be not having knowledge,budget or laziness any Waterproofing System will fail if what is underneath it isn't adequate.An extra day or so on structure,plumbing and install can save you thousands of dollars in the future.Thank you for keeping our Trade strong.

Great video. What do you recommend if you do a flood test and you see a leak?
Ardex 8+9 over Kerdi? Terrible idea? Or unnecessary but harmless belt and suspenders insurance? Many thanks.

Leave a Reply