laundry/water heater closet waterproofing
I have a 7.5′ wide x ~34″ deep closet space along the hallway at the top of my stairs for my water heater & washer/dryer.
I’d like to waterproof the floor and add a floor drain. I suppose I could use pans, but in the past it was hard to get the unit in or out of the pan without damaging the pan, and the pan only helps if the leak actually drips into it. So waterproofing the whole floor and wall base seems like a better solution.
Other relevant details:
– it’s plywood subflooring
– I’m planning to use 3/4″ hardwood in the hallway
– for the closet doors I’m leaning toward using johnson hardware for a multi-slide door (so 4 panels like a regular double bi-fold, but they all slide to the same side). This way they slide against a wall and don’t obstruct the hallway when open.
My question is, does anyone have any ideas for a good way of waterproofing the closet?
– would you slope the floor? Or just rely on a dam across the front since it’s just an emergency drain?
– is tile with a membrane underneath the best flooring option? Or would something like sheet vinyl work? (a key question with the vinyl is how would I waterproof up the base of the wall?)
– what would you use for the threshold, and how could I keep the height to a minimum? (so it won’t interfere with the doors and be less difficult to slide a washer in & out over)
– OR does it make sense to design the whole closet floor like raised platform that the doors & washer sit on top of, and allow leaks to drain through to a sloped liner and floor drain underneath?
Thanks for any input or ideas,
Ben
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Replies
Kerdi membrane right up the walls. Integrates to a drain, put some plain tiles down. Works for showers
Thanks. Can kerdi membrane go direct to plywood or do I need a mortar bed or cement board underneath? If I use schluter was thinking I'd use their Floor drain F with ditra.
Yes I would use ditra on the floor and Kerri band up wall, with Kerdi drain f. Ditra bonds direct to subfloor. For your threshold I would go to the tile store like floor and decor and pick out a ceramic or porcelain tile for the main flooring and then see if you can find a real stone that matches to use as the threshold, as these are generally thicker. You can then ease the edge with a stone round over bit on a router or grinder. I think you could get just a slight raised threshold this way.
Sounds good. And how would I waterproof the ditra to the stone threshold? Do I attach the stone with thinset like the tile? Is silicone enough to waterproof it? And if so, where does it go? Also, would you slope the floor or just leave flat? Thanks!
Sorry I meant a stone tile, like a slate, limestone, marble…
In this case the dittra goes under this as well. 95% of water will drain on top of tile so having a back dam on the dittra level is probable not necessary. If you aren’t able to get the height difference you want with the stone you could add a strip of 1/4 or 1/2 ply under threshold portion, them use Kerdi band to tie into dirta. This would give you that dam on the waterproofing.
I think some companies even make a foam threshold piece but I think kerdi only makes one curb height.
Waterproofing the floor, with a front dam, to contain water spills seems like overkill if the primary concern is avoiding damage to a pan when getting the washer into it. I have a similar washer/dryer closet, although deeper than 34", and the washer sits in a pan that is more like very stiff rubber than rigid/brittle plastic. Getting the washer into the pan isn't something you do often. If the only problem is to slip the pan under the washer with the washer already in place:
1. Move the dryer out into the hallway if needed to make room to work; these things are lightweight and easily moved.
2. Pull the washer forward onto its front feet, and slide a 2x4 underneath the rear feet.
3. Lift the front of the washer and slide the pan underneath it as far as the 2x4 in the rear; lower the front feet into the pan.
4. Pull the washer onto its front feet a bit, and with side-to-side motion pull the washer forward at least until the rear feet can be lowered into the pan. Remove the 2x4, position the pan and washer as far back as needed for hose clearance, and put the dryer back into place.
If there are any other leak sources that won't drip into the pan, it's easy enough to tape a sheet of poly to the wall, with the bottom edge hanging into the pan. Or just make sure you have good hoses, a good idea anyway, since a pan or waterproofed floor won't contain a flood from a hose rupture.
What I have done in the past (and this isn't something that comes up very often), is to have a sheet metal shop fabricate a stainless steel pan out of reasonably heavy (0.050" or so) 303 or 304 stainless steel, with welded corners. This is a simple pan, with a 1" or so wall around the edge. I have sometimes had a drain port welded onto one side. Rolling the top of the side wall is nice to avoid the narrow edge, but not all fab shops have the ability to do that.
Put a liquid sensor in the pan. The sensor will now trigger if there is a leak, and the pan will contain the leak while you work to shut the water off. This works well for the usual small leaks. Huge leaks are going to overflow anything you do unless you plumb in a "real" drain, and I suppose you could do that with the stainless steel pan although I've never gone that far.
The pan can sit under the water heater, and anything else (you can get it made to size), and it can sit on top of anything. I normally just sit the pan directly on the subfloor or slab.
I don't think it's worth all the effort to build out what is essentially a shower stall in a mechanical closet.
Bill
I haven't done a 'new' install of a HWH and Washer in almost 30 years, but is there a code requirement for a drained pan? If you have priced SS recently they aint giving it away
There is for a hot water heater, but not for a washer as far as I know. The usual pans sold for water heaters are round aluminum pans. I don't particularly like aluminum for this since it's more prone to corrosion over time, stainless steel holds up better but I've never seen a ready made stainless pan for this application.
Bill
Killarney Metals make some ready-made round stainless water heater pans. They're local to me in NC, which is why I know this.
They also make some open front washer pans, washer pans with drains, and SS washer pans.
...and the ultimate in washer pan fanciness, an open front pan with a trench drain. It's a 3-sided luxury shower base for your washer, basically.
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I second Bill's solution, although an aluminum or galvanized steel pan would probably be a lot cheaper. You can paint it to prevent rust. I have such a setup for my washing machine and it drained pretty well to the outside when I tested it.
For the front "dam" of mine, I have a 2x4 against the front edge of the pan, which supports it against damage from moving heavy appliances. The other 3 sides are backed up against the wall.
Aluminum will be more than stainless steel, galvanized steel cheaper. Stainless steel isn't nearly as much of a price premium as you'd think when you go through commercial channels. Hardware stores just gouge a lot for stainless steel hardware. For me, commercially, as one example, stainless steel pipe is cheaper than copper pipe in applications where I have it as an option. Stainless steel is usually cheaper than aluminum lately too, due to huuuge price increases on aluminum after the pandemic.
Bill
Per mcmaster carr, stainless sheet is twice what the same size 5052 alu is[4x4x.03 ss 199.50 to 91.94 alu]
mcmaster is 50% to 100% higher than my local supply house, but in general consistent. The cheapest sheet of 4x8 ss is almost 300 before shipping from mcmaster. Now assuuuuuuume a sheet metal house paid 150 for that sheet before touching it, but what are they going to sell it to you for? I too would prefer it over aluminum, but I am starting to wonder, when you can get tile for under a buck a square foot, and the tile guy is there already.
My pricing is wholesale as I have an arrangement with my fab shop (I do some engineering work for them, they give me smokin' deals on stuff when I need a small thing done). Stainless isn't usually much of a premium, if any, over aluminum. We do buy a lot more stainless than we do aluminum though, so volume prices might come into play a bit -- I haven't really looked into that.
This is something you want to last forever though. Stainless steel is less likely to corrode out over time compared to aluminum, and especially compared to galvanized steel. I'd go with stainless just to know I wouldn't have to replace it -- ever -- even if it cost a little more to do. Labor shouldn't be any different either way, so it's just a materials cost issue if anything. I typically use 18 gauge 303 or 304 stainless for these pans. 316 works too, but it's more expensive and not really needed here.
Bill