Zero Threshold Shower
idahobuild
| Posted in General Questions on
Hello All,
Looking at the plan for the master bathroom, we have details showing the 3″ recession of the conc. to accommodate a zero threshold entry – with no door. Currently, the 3″ drop extends from the wall with the shower head (east wall) all the way to the west wall. It seems like the the pan should/could just stop at the end of the 3/4 wall that makes up the showers southern perimeter (see atch’d).
Can we adjust that dropped area of conc. to be a smaller area?
Thanks.
WD
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Replies
Short answer = No.
The showerhead and use of the shower will spray water far past your blue line. You want everywhere the water hits to slope to the drain.
So if you want a no step shower, the entrance to your shower has to be flat. So first, the dashed line next to the yellow arrow needs to be totally flat - it cannot have any slope. So you need to figure out how you will get your slope. You options include:
a. Make it like a bowl, where the perimeter is all at the same elevation, and it all slopes to the middle with a drain in the middle. In that case the left part needs to slope just as much as the right part.
b. Make it all slope to a slot drain on the wall opposite the entrance to the shower. In this case the left part needs to slope just like the right part.
The good news is the size and geometry of your shower looks great for a no step/zero threshold and no door/curtain shower.
I built one with a cross slope to a slot drain the runs the entire length on the wall opposite the entrance. That part works great. Mine is 3' 4" wide, which is also sufficient, but it is only 5' deep, which is somewhat insufficient for a set up with no door and no curtain. I have a 3' wide entrance (where yours is 4'8"), and a 2' walled portion (where yours is 4'6"). Water bounces all the way to the back wall, and out the door opening. I think you will have water bouncing past the 4'6.5" wall and out the opening. If you can extend that wall and make the opening only 3' wide, you will reduce the chances of this.
Also, with your setup, if you slope the entire thing, you will be able to have a handheld shower, because those have the potential to spray everywhere.
1. Make a smaller shower and keep the slope.
2. Get rid of the no curb shower.
If having no curb is because of an accessibility issue, I fully support it. If it's anything other than that, I find it to be a fussy, risky detail that adds a lot of money in a small area.
I've seen a lot of these zero threshold showers in various publications, online features, etc. They always look nice. Then I stayed in a hotel with one and it was the most frustrating silly thing I've ever experienced in a bathroom.
Patrick - many people who current do not have accessibility issue may have them in the future. The US especially is an aging population; a no step shower in a bath on the first floor makes the home infinitely more useful. Even younger and middle aged people can get injured (fairly difficult to get over a shower step for a person with a broken leg & arm), younger and middle aged able bodied people may have relatives with mobility issues whom they want to host, and many people would like to age in place in their homes. No step showers are immensely helpful in accommodating all of these issue.
The fact that the one in your hotel did not function properly does not mean none of them do. There are many ways to make them functional, and when built properly they are very convenient. Every home with a ground floor bath/shower should have one.
Just thinking out-loud...
These showers are usually built on a 3" recessed slab with a membrane and sloped mortar bed. What would happen if you just sloped the main slab, used a ditra decoupling membrane and tiled the whole bathroom floor?
Malcolm,
You could, it becomes a labour issue. Are your concrete people good at sloping the slab? This would requires some intense details in sloping formwork against the main slab, And the drain detail would have to be perfect.
Vs just boxing out the area with a form and doing a simple 3" depression. And let the tile people create the slope and manage the details.
I personally hate tile and will always opt out of it in the design phase, so I'd do the former myself. But not many else do.
Patrick,
I get what you're writing. I've had some 'fun' experiences with curbless as well. However, I personally hate thresholds in general, even transitions on wood floors. Just a feel thing. Maybe because I don't wear slippers or indoor shoes...
But I've become keen on the idea of a ¾" step down Into a shower area. So it's not quite curbless, but it functions the same as a threshold and much better look and feel. Hard to achieve on wood floors through.
Jamie
Jamie,
Good p0int. I guess without a membrane you also have a weak joint between the floor and the walls.
I like the idea of a 3/4" curb, which isn't much of an impediment to disabled access.
I have had curbless doorless showers in the last two houses, and they added little to the real cost of the project
You put a towel down anyway, and there is little spray beyond that IME
I'm gearing up to replace my clawfoot bathtub/shower with a tiled shower, in a similar arrangement to yours. I don't trust fully flush thresholds; I've seen and fixed too many clogged drains, but I also don't want a raised curb or long-term moisture damage. I plan to use a linear drain at the far right, under the showerhead, and slope it up uniformly to the left end, where the step down into the shower will only be about 1". Maybe something similar would work for you.
Small would be worse. Stub your toe constantly
Calculate the water volume of the shower enclosure and worry less
Current shower has a linear drain, 13 years no clogs
Previous had central round drain, again , never clogged.
I think tubs tend to clog because of the stopper mechanism, showers not so muc
My worst experience with a zero-threshold shower was at a hotel. The only room available was the "accessible" one and I was looking forward to a long shower. When I got out of the shower, the water was over the top of the 3/4" threshold into the main room and starting to pour over onto the carpet.
For my bathroom, I'm balancing a lot of priorities, including having it be somewhat wheelchair accessible (just in case), so the possibility of it being a toe-stubber is one I'm willing to take. Our house is almost 200 years old with lots of floor height changes so it might be different for others.
I agree that drain stoppers are the main culprit for catching hair; I have very little hair but my wife has more than enough to make up for it. Our septic tank is prone to clogging; we have it pumped every 3 years but I have to dig it up to clear a clog every year or two. The amount of storage in a typical zero-threshold 30"x60" shower is somewhere around 5-8 gallons. That means 2-3 minutes of warning if the drain is clogged. That's not enough to make me comfortable with the idea of a zero-threshold shower. My design will provide about twice that much storage.
Michael
Good points.
My home has a curbless shower without door or curtain, and I'm very happy with it. There are a few things I would do differently if I were to do it again, but none of the issues makes me think a curb would be better.
I detailed the design of my shower in response #1 above. To be clear, the slope in my shower is across the 3'4" dimension to a slot drain that is almost the entire 5'0" depth. The total drop across the 3'4" is 1 1/8" (less than I thought but just measured...). The slope is not noticeable when standing in the shower - due to the direction of slope vs showerhead, one foot is usually on the lower side than the other foot.
The things that are great: ease of getting in and out, no glass door to clean. The shower floor is 1x1 tiles with epoxy grout. The 1x1 tiles provide sufficient surface variation so that the wet floor is not slippery. The epoxy grout reduces maintenance - it definitely needs less maintenance than regular grout
The things I would change: The entrance is 3' wide, and the tile extends about 5" past the 3'4" width at the entrance. Given the dimensions of my shower, this is not far enough. So my ideal reconfiguration would be to make the shower much deeper - ie increase the 5'0" dimension. Since that was not possible in my case, I would extend that 5" waterproof entrance to 12". However, if that 12" were tile, it would be cold, since that section of tile will not be warmed by the hot shower. SO, I would recess this 12" x width of entrance section deeper than the shower entrance elevation, and install a drain in this 12" section. I would configure the depth to accept a wooden mat, and for the finish elevation to remain flush with the mat inserted. By mat I mean something like the Ikea deck "tiles" (https://www.ikea.com/us/en/p/runnen-decking-outdoor-brown-stained-90234226/). This would get me a not visilbe secondary drain (which although spec'd & priced my builder did not install) that collects any overflow before it gets to the rest of the bathroom, it would give a transitional surface that is not as cold on the feet as tile, and would eliminate the need for a bath mat in that transitional space at the shower entrance.
In regards to the slot drain, the particular brand they used at my shower has a small (2"?) diameter drain, with a plastic basket insert. This basket insert does exactly what it should - collects hair. But I've also realized it quickly clogs as a result of conditioner that is used on my house. The users of conditioner have drastically reduced the amount they use, so I now only need to clean this plastic basket about every 4-6 weeks, instead of every week (which was the situation when I first moved into this house). However, to access the plastic basket for cleaning, I have to lift the top of the slot drain, which is my case is tiled, and a bit heavy. It is also a bit of a pain, but I do it religiously since my bath does not have a secondary drain. I'm hoping that by the time I age enough for this chore to become difficult, I can locate a conditioner that does not clog the basket so quickly. I would get a non-tiled top to the slot drain next time. Even though it may not look as cool, it would be easier to clean.
Regarding the basin filling, mine gives more than 5 minutes of showering from when I first notice it may be getting clogged (I see the soap suds are not draining as quickly) until the basin fills so much that I MUST turn off the shower. My showerhead is a 1.75 gpm showerhead (and it is GREAT). I calculate that my basin holds about 2700 ci, and the drain trough holds another 155 ci, so 2855 ci total, or just under 12.4 gallons. So if it is TOTALLY clogged, that is over 7 minutes of showering. I would still be far more comfortable with a secondary drain... to address the potential catastrophic issue, I have a few water sensors in various places nearby that automatically shut off the water to the house if they are triggered, so although there could still be damage, it is hopefully limited.
I think I would just use the extra inch with a steeper pitch to the drain. I have a feeling the today you considers a 1 inch step accessible but the 87 year old you possibly might feel different
Clogs in the tank?
Yow something besides hair going on there
I appreciate your concern but I am confident with my design decisions. I was sharing it to give Idahobuild a possible alternative, not for critique. Yes we have a somewhat unique situation that results in more toilet paper than average going into the septic tank, and because we live on a 500' hill of solid rock, there is not much pitch from the fixture to the tank to the leach field. But I have been building, renovating and/or designing homes for almost 35 years and I have seen other tanks clog on occasion. When ours first clogged, I thought it was the pipes and asked our local plumber if he'd check it out. He went straight to the septic tank.
For anyone interested, shower floors must slope between 1/4":12" and 1/2":12" https://codes.iccsafe.org/content/IRC2015/chapter-27-plumbing-fixtures#IRC2015_Pt07_Ch27_SecP2709
In my bathroom, which I completed 2 years ago, I've got a space about 7'x7' with a tub built into the corner, a 3' glass panel adjacent to the showerhead and the entire space slopes to a circular drain about 18" in front of the shower head. It works great and gives me loads of space to move around. I can use the edge of the tub like a stool. I set the tub as low to the slab as possible, with a recess for the tub drain.
It's all totally curbless. I'll definitely be repeating this design in a few years when I expect to move again into my final retirement house.