Shower Renovation Questions

[nelsonxn]

Hello,
I rebuilt my shower to be curbless so i need to dam up the him/her sides of the shower floor for a water test.

My question is... what do i use to hold/glue the two 6"x5' boards coated with Mapei AquaDefense membrane to each side of the shower openings that's removable without damaging or leaving a residue on the AquaDefense membrane applied to the shower floor and walls? (FYI, AquaDefense membrane not applied yet.)

For instance... hot glue gun, plumbers putty, silicon caulking...?

the shower pan is a Schluter Styrofoam pan with Kerdi-band sealing the edge between the pan and hardiebacker hydrodefense cement board walls and Henry self leveled his/her floors.

image attached... I have not rolled the AquaDefense membrane onto the shower walls and floor and bathroom floors yet.

[cx]

Welcome, Nelson.

I'm curious to know what we'll be testing with this damming procedure?

First, I suppose, we should know if you're required by your code compliance inspector to do the damming of the two entries as you're proposing. If not, then I'm not really seeing the usefulness of your testing. Yes, we (TYW) generally recommend testing of site-built shower receptors for waterproofing, but your construct seems to allow for no actual flooding deeper than the outflow at the higher of the two openings in the shower under even the worst possible scenario of plumbing obstruction.

Do you plan and enclosure of some kind on either entry that might actually create a damming action? If not, and if not required by a code compliance official, I would simply ask myself two questions: Did I use the correct materials? Did I install them in a workman-like manner in accordance with the manufacturer(s) instructions? If I could answer yes to both, I would eliminate the flood testing all together. See my warranty information below.

You appear to have a Schluter membrane on the shower floor. I would not recommend using any liquid-applied membrane over that. Not sure just how you're supposed to finish those walls, but I'm not sure I'd want to paint a different liquid-applied membrane there, either. But that's:

My opinion; worth price charged.

[Kman]

Welcome to the forum, Nelson.

Maybe you should clarify this part of your post:

the AquaDefense membrane applied to the shower floor and walls?

It seems you're putting AquaDefense on the floor. Is that correct?

[ss3964spd]

Well, I could have suggested what to do before you got to this point but that won't help you now, Nelson.

I can't really think of anything you could use to effectively seal your dams yet be easily removeable without a trace. If your goal is to test the drain you could just fill the pan until it gets close to the openings. The water won't be very deep, of course, but should be sufficient to tell if the area around the drain is sealed.

[nelsonxn]

TO Cx, Kman and ss3964spd, Thanks for responding...

Schluter recommends a flood test even for curbless showers by damming up the open sides. Search for "schluter curbless shower flood test" on YouTube.

Yes, i have a Schluter shower pan that has the kerdi waterproof membrane already attached. I bought the shower pan mainly for the built in slope, it's just a plus that it has the kerdi membrane already on it. I also bought the Hardiebacker hydrodefense cement board thinking the waterproofing was just added protection.

I get the feeling that i did not use the right materials and should of used a presloped shower pan and cement board without embedded waterproofing.

Yes, I'm going to apply the AquaDefense liquid membrane on the entire master bath floor including the shower pan floor and shower walls.

Also, I don't care about any Schluter, Mapei or Hardy warranties since this installation is not based on one manufacture's system.

I talked with both Schluter and Hardy and they both said it would not be a problem to cover the Hardy hydrodefense boards and the Schluter shower pan with the Mapei AquaDefense liquid membrane, it would just be redundant.

Also, the mortar was applied at least 48 hrs ago and should be dry.

What are your concerns about applying the liquid membrane over the Schluter pan and Hardy boards?

[ss3964spd]

I wouldn't hesitate applying the AD over the Hardie, especially over the Kerdi band to Hardie seam (Hardie lacks the surface fleece which plays an integral roll in water proofing Schluter's Kerdi), and assuming there is no water proofing behind the Hardie. I'd be much less inclined to apply AD over the Kerdi tray. Besides being redundant/unnecessary, I'd rather bond tile to the Kerdi fleece than to a roll on membrane. If you miss something, like a pin hole in the AD, you'll get water between the Kerdi and the AD with no real way for it to get out. Would that be a big deal? I dunno.

I assume the bathroom floor is concrete. What's the goal of applying AD to the entire bathroom floor?

Still can't think of a reasonable solution to your initial question.

[nelsonxn]

To ss3964spd,

I applied HENRY 542 Liquid Backer Board Self-Leveling compound on both my and my wife's side of the master bath floors because the floors were not level and it allowed me to match the height of the master bath floor to the shower pan edge so the shower and master bath floor tiles will be even when installed.

I wanted to waterproof the master bath floors just to cautious in case the drain plugged up during a shower and water ran onto the master bath floor. I didn't want water seeping through the mortar then leveling compound and onto the OSB subfloor.

[Davy]

We cover most slabs with Auqa Defense as an anti-fracture membrane since every slab in Texas seems to have a slab crack somewhere.

[ss3964spd]

Nelson, if the rest of the bathroom floor is concrete, as it looks to be, water isn't going to bother it at all. Certainly no harm, aside from time and expense, in AD'g the whole of it though.

[nelsonxn]

the master bath is on the second floor of our home. The subfloor is OSB coated with Henry primer and then HENRY 542 Liquid Backer Board Self-Leveling compound on top.

so at this point there is no consensus on...

1. what sealer to use to keep the dammed water from seeping around or under the dam board during flood testing that won't damage the AquaDefense when the dam board is removed.

2. whether it is a bad idea to AquaDefense over the Kerdi shower pan.

[Lazarus]

If it gives you a "warm & fuzzy" feeling, I see no reason why you could not set a piece of foam (or a 2x4) in the opening and seal it with some silicone caulk temporarily to do a flood test. By the same token, you can simply do as SS396 mentioned...you can "go with what ya got" and flood test up to the ramp and you should be good to go. I've never had a properly set Kerdi floor to leak.

I suppose you could paint a seal of HydroDefense from the Kerdi band up slightly from the band to the wallboard for insurance....

You are, of course, combining a couple of different waterproofing systems together and, will get no warrantee from any of them...but it seems as though that is not an issue with you. Superficially, I would imagine you are good to go....but don't paint the HD over the Kerdi floor. Not necessary. (IMHO)

[ss3964spd]

As additional details emerge we're better equipped to offer ideas and guidance.

The SLC isn't going to be bothered by the water. If part of your reasoning for AD'g the entire floor is to contain overflow water then you'd also have to seal the wall to floor joints around the entire perimeter of the room, as well as create a dam of some sort at the entry.

I don't think there is any conclusive evidence that applying AD over the Kerdi tray is a bad idea. What we do know this that, correctly installed, the Kerdi tray (and drain) are water proof on their own. We also know that trapping water between two water proof layers is undesirable. What you choose to do with that information is up to you, natch.

As far as the dam for testing goes; AD isn't likely to adhere to any surface very tenaciously. Given that, I think you could probably just use their fabric and liquid to seal the board to the Hardie and the Kerdi, then just peel it off after your test. Place some heavy objects behind the boards for some support. After removal you can just roll/brush on another layer or two in those areas to seal up whatever may have been peeled off.

[nelsonxn]

Thanks for all your comments and suggestions.

1. I think a thin bead silicon caulking will do as a sealer for the dam for flood testing.

2. It looks like I really don't need any additional waterproofing since I used the waterproof Schluter kerdi pan and Hardy Hydrodefense boards for the shower walls. I'll mull this part over a little longer.

3. I agree that it really wouldn't do any good to apply AquaDefense on top of the leveling compound that's on top the master bath subfloor floor since i can't dam the master bath entrances in case of a flood, unless water can seep through the tiles down to the leveling compound and then to the sealed OSB underneath.

[ss3964spd]

I wouldn't use silicone, Nelson. You won't be able to remove all of it and nothing will adhere to whatever is left. Not the AD, nor thinset mortar.

As a daily user of a curbless, doorless walk in shower the reality is A) drains don't go from free flowing to instantly clogged. Users will notice if the drain is slow by the amount of water they are standing in. Plenty of time to take corrective action. B) if it does clog to the point of over flowing the pan while in use, yet goes unnoticed, something is probably tragically wrong. If A or B are real concerns then it isn't too late to install water containment curbs.

[nelsonxn]

Yea, maybe I'm over thinking the waterproofing issue.

I guess you all would agree that having the waterproof Hardy Hydro defense cement board shower walls and the waterproof Schluter Kerdi shower pan should be enough protection for the shower and i should just start tiling.