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trench drain

Mpj Member Posts: 109
I'm doing a stall shower that is 8' X 4', the customer want a trench drain to go along the entire back wall(8'). Looking into different types of drains and nobody has one that long. I can put two together with a factory made "splice" piece joining the covers together but their are two separate 2" drains coming out the bottom. My question is, can I tie both drains together before the trap or do i need two traps(one on each tailpiece?


  • MikeL_2
    MikeL_2 Member Posts: 291
    larger length / width linear drains are available.....


    Try Schluter, their Kerdi system has channels / grates up to 72", and larger, custom sizes are available. Infinity Drain has units up to 96"...........
  • icesailor
    icesailor Member Posts: 7,265
    Trench Drain Showers:

    That sounds like a custom shower pan/floor. Unless you can find something that fits your needs exactly, can't you not use a vinyl shower pan liner and fabricate exactly what you want? They also have some improved and more advanced shower pan floor systems. You would need only one drain, a standard drain for liners or pans, you can slope the water into the drain, make any curb you want, and tile the whole shower any way you want. I don't understand why you might need two drains.

    Putting a gutter drain against the back may not be such a good idea because it will have to be wide enough to fit the base of the drain in, and someone could step in it accidently and suffer an injury.

    There's a proper way to do shower pans. Many are not done properly.
  • Zman
    Zman Member Posts: 6,958

    Check out these guys.

    Very nice product
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Mpj
    Mpj Member Posts: 109
    trench drain

    Thanks for the replies. The customer want a trench drain, I will look into the mentioned products.

  • icesailor
    icesailor Member Posts: 7,265
    edited August 2014
    Be sure:

    IMO, be sure that the customer picks out what trench type drain they want and don't YOU do it.

    I work from experience. Any one of those trench type grid drains will be a nasty mess in a shower floor setting. From soap, shampoo, skin and body secretions, they will become really skanky after time and can really smell. They will be hard to keep clean. To clean any of them will require removal of the grid and going after it with a old toothbrush and bathroom cleaner. AND the inside of the gutter drain. While wearing gloves.

    If after some period of time, the bathroom develops a strange odor, it will be coming from that gutter drain and metal grid. In some jurisdictions, it might not even be legal.

    Then, there's the issue of can it be installed correctly so that the space has a pitched under floor with the liner sloped and on top of the under floor. So that any water that seeps down ends up in the drain and not on the under floor. Where that water becomes "biological" and smells like a septic tank from all the active anaerobic bacteria. If you've ever ripped out an old leaking improperly installed pan, you know the smell.

    Some of the photos in the links are installed disasters. Especially ones with the drain running across the middle of the floor. Its wiser to keep them along a wall. or at least the width of a tile away. If it runs across a slope, you have to bend it. Then, make it keep the bend and lay flat. Tile setters are experts at tiling vertical surfaces. Horizontal flat services not so much when it comes to pitch. To them, "pitch" is more of a musical term than a term we use to denote slope to carry water away. With large area floor spaces, it becomes hard for them to avoid "ponding" in places because of a lack of slope. And too much slope makes it hard for some people to stand on the floor. Especially if they are old and/or have problems with balance. Make sure that they use tapered wooden screeds on the top pour and make it with mortar that is really stiff. Like just enough water to pound it down. If they male it like soup or chowder, a large floor can crack.

    Once you tell them all that, they will think you are an @$$hat and an idiot. They will be nowhere around when you find some of the above listed things. We all know that just because someone smarter than us, with far less experience than us, doesn't mean it will work.

    The installation video covers everything I said. It is approved in all jurisdictions.

    It is NOT generally accepted good practice to put backer board below the pan floor where it will wick water and rot the wood framing. As I have seen.

    One who stands in water when taking a shower on a 32"X60" tiled shower with a curb and barely pitched floor.