Hidden stub-out for shower drain?

Discussion in 'Shower & bathtub Forum & Blog' started by stephenson, Nov 29, 2011.

  1. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    3000 SF house built in 1995 in Virginia ... generally modern building techniques - including polybutylyne that was completely replaced with CPVC well before we bought the place.

    Basement level is walkout to the back - house is on a lake with a septic tank and pump system that pumps liquids about 500 feet back to the front yard area drainage field. A half bath is about 2/3 of the depth of the house from the back wall with a family room and hallway between it and the back wall.

    The bathroom did not have a shower or tub, but did have a closet framed in a finished directly in front of the tub - and, shaped and sized about the same as a shower ... I figured no way would be lucky enough to have it stubbed out for shower ... floor and inside closet carpeted with short pile carpeting. I pulled carpeting up and found a 2' square concrete area dead center in the middle of the closet that was poured separate from the remainder of the basement ... so, I tapped on it with framing hammer noting different sound and then whacked the center of the comcrete square.

    The center easily tapped out to a round shape with a plastic container with the bottom up - I pulled the container and removed a bucket of sand and stone to find a capped (glued on) 2" (it may be 1 1/2") PVC pipe heading towards the back of the house (there would still be room for the pipe to turn in the middle of floor and go to one of two different waste pipes). Is this a typical "stub out" wherein you wanted a flush floor?

    So ... given no plans to review, and planning to make the room a "wet room" with shower tiled with level floor for handicap accessibilty, I was going to remove the remainder of the concrete in order to further investigate ... it's the next step I need help with ... do I just cut off the PVC cap and build up a temp PVC about the height of the future drain and see if it drains - listening along the floor to determine where to?

    Any other comments would be very much appreciated!
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    Often, they do not install a trap...you'd want to verify whether one is there or not. If there is one, you'd pour some water down it, then look to see if you can see any standing water that should be held by the trap, if it is there. Then, you need to determine if the pipe is really 1.5" (which is okay for a tub), or 2" (which is required for a shower). In some places, they require at least 2" pipe below a slab.

    If you want the whole room to be handicap accessable, with a barrier free shower, then you either need to recess the shower area, or build up the floor with to allow for proper drainage. It's nicer to recess the thing, then there's no ramp coming into the room. An accessable shower begs for a linear drain, but your stubout is in the wrong position for that (might be easy to move). With a linear drain, you can slope the entire floor, so no need for multiple pitches.
  3. Terry

    Terry Administrator Staff Member

    Messages:
    14,783
    Location:
    Bothell, Washington
    When I rough for a future shower drain, I leave the horizontal trap arm below slab, capped off.
    When the shower pan is installed, then a p-trap can be located properly and then glued on.

    You may be able to find 1/2" stubs in the wall that were left for a future shower valve.

    And yes, you can run some water down that pipe and make sure that it all drains before you get too committed on the plan.
  4. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    Thanks, Guys ... since the capped off end is about a foot below the finish concrete grade, I have a feeling it's a trap arm ... the capped end is also slightly off center, as well. Here's to hoping I can get it to drain ... I'll probably run quite a lot of water through it to make sure someone doesn't have a macbre sense of humor (not connecting the pipe to anything further under the slab :))

    If it is a 1 1/2" below the slab .... what are my options? Test with lots of water flow and go with it?

    BTW, I think I'll excavate for a fully recessed shower ... did some reading and sounds in general like: (1) excavate (maybe even a bit further than shower area itself), (2) install trap and vertical extension, etc, (3) concrete to below grade, (4) install liner, (5) concrete back to grade with slope to drain ... I like the look ...

    Thanks!!
  5. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    Forgot to say - no stubs for supply lines, but they are way easy to get to ... especially with CPVC ... weird looking stuff for plumbing, first I've had ... repiping installer not very neat in runs with many runs snaked in and out of pipes and wires ... not used to seeing "rigid" plastic bending and hanging ... been that way for years, though ....
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    The liner must be on TOP of the preslope, otherwise, it just acts like a basin to collect any moisture that slowly accumulates. Without a slope to the drain, the moisture there can't drain (through the weep holes of the shower drain). Contrary to popular thought, the LINER is the waterproof layer, not the tile, so it needs to be sloped too, then tile ends up sloped to take the majority of the water to the drain.

    There are surface waterproofing materials, both sheet goods and paint on that can be used so that you don't have to make another layer above the traditional embedded shower liner. My preference is Kerdi www.schluter.com, but there are others. Ask, and you'll get lots of opinions. they all work if installed properly. Surface membranes also have the advantage in that you can extend them outside the shower with little problem, and essentially, make the entire room a 'wet' room. Consider a wall-hung toilet, then the potential slope in the room isn't as big a hassle, and you can more easily mop underneath. check out www.johnbridge.com for some ideas and help, too.
  7. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Fully recessed shower or barrier free shower

    Post(s) deleted by John Whipple
    Last edited: Mar 18, 2014
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    Drop a trowel onto a surface membrane just right, and it doesn't matter what thickness it is, you'll likely poke a hole. same thing with anything sharp. The nice thing about Kerdi, is the patch won't make a big lump. And, it's easier to minimize buildup in corners. But, any of them can make a good shower.

    Some people will swear that porcelain tile requires a modified thinset, but that's bunk. If you technique is good, a quality dryset will grab and hold nearly any tile you can think of (some glass ones are an exception) with far more strength than needed for any install. Look at the specs on a good dryset, extrapolate that to a normal sized tile, and it can take TONS to shear it off once cured. Whatever you do, engineer it right, use quality materials (that doesn't necessarily mean expensive), follow the manufacturer's instructions, and don't take shortcuts. It'll work.
  9. Widdershins

    Widdershins New Member

    Messages:
    7
    Location:
    Washington State
    If it proves to be an 1-1/2 trap arm, then you should take it back to the 2" Tee or Wye fitting it extends from.

    OTOH, from it's described location (the middle of the opening) it was likely intended to be used for a shower and is likely sufficiently sized.
  10. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Post(s) deleted by John Whipple
    Last edited: Mar 18, 2014
  11. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    You guys are great - thanks ...

    I'm a bit remote in this geographic area - both remodelers I have spoken with didn't appear to have good handle on a flush tile floor concept ... I'm also looking at the option of a a low lipped fiberglas/resin base/receiver and either integral wall panels or tile ... sort of a mid way solution. Did a 3x5 shower a few months ago with a shower receiver and subway tile and turned out very nice ... this would have to be wider, but looks like there are several manufacturers that build this sort of receiver ...
  12. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Post(s) deleted by John Whipple
    Last edited: Mar 18, 2014
  13. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    John, you seemed to miss the comment where I said follow the manufacturers instructions. There is a lot of heresay that says you MUST use a modified for any porcelain tile...well, that is bunk, unless the manufacturer says so. On that tile, the additional specification for using white has nothing to do with the kind of thinset, but that the tile is somewhat translucent, and using grey would discolor it. Don't try to twist my words, and no, as far as I know, my portfolio (I don't manage it) contains no stock in Schluter.

    As I understand it, Schluter's concern on the use of modified thinsets is a potential problem where the modifiers may take a long time to dry out when you consider that the membrane is waterproof and a large tile (porcelain or glass) is essentially waterproof too. If a mortar bond is disturbed before it is dried and cured, you CAN compromise it and break the bond. By no means is this a certainty. This is essentially true with ANY waterproof surface membrane. It's just that Schluter is being proactive and warning people about it. As with anything, choose to ignore the manufacturer's recommendations, and you take the consequences. Whether it WILL happen is a combination of circumstances, but Schluter has made the corporate decision to ensure your install will succeed, a dryset mortar will ALWAYS work, if appropriate for the materials being set.

    On initial tack, a modified thinset IS stickier. On a large tile, if you don't burn a coat into the back, you have a higher probability of good bond with a modified. If your technique is good, you'll get a very satisfactory bond with a dryset.
  14. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Post(s) deleted by John Whipple
    Last edited: Mar 18, 2014
  15. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    Quick update .... did a bit more excavation to clear cutting room ... temp installed a 90 and extension ... ran water hose from outside and checked liquid septic tank (I pump from back yard to front) for sound resonating from septic tank ... I got flow!! Backtracked and pulled cleanout to determine which it went it to ... I'm in business! Way better than the alternative!!

    Will review measurements for turnaround and see which solution will work ... Thank You All, again ... will status!
  16. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    The amount of coverage you get on the back of a tile is entirely a function of the craftsmanship, not the type of mortar used.

    Comparing the shear strength (what it would take to shear a tile off the substrate) between a good dryset and a modified (I chose to look at Custom's products, but others are similar) shows a shear strength (after a standard 28-day cure) with dryset of 244psi and 375psi for their modified. While that may look like a useful difference, consider this...with a dryset (this was on porcelain, other tile types would differ in the bond strength), on a typical 12x12" tile, that's 35,136 pounds or over 17 TONS. Before the thing sheared off the wall (or floor), the structure would likely have long since failed.

    I've seen some glass and other tile in Jordan that was over 2,000 years old...still intact, walked on for millenia. They didn't have thinsets back then, only cement. The Romans knew how to build things to last. They also had good craftsman. They had to be otherwise they may have been sold into slavery or fed to the lions (wouldn't it be nice to be able to do that with some of the hacks out there - craftsmanship quaility would improve dramatically)! I don't feel deprived by having to 'only' use a dryset with certain products. And, if you could get in contact with someone who knows at a tile producer, they'd probably allow you to use a dryset, if you really wanted to, and it was specified. But, you should follow the manufacturer's instructions - it doesn't hurt to actually ask them why or for dispensation, though.
  17. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    Oh yeah ... forgot to say ... it was 2"!
  18. johnfrwhipple

    johnfrwhipple I love these ACO Shower Drains - Best in Class

    Messages:
    3,810
    Location:
    North Vancouver, BC
    Post(s) deleted by John Whipple
    Last edited: Mar 18, 2014
  19. stephenson

    stephenson New Member

    Messages:
    69
    Location:
    Northern Virginia
    Haven't posted photos here, before - could figure it out, but am sans camera at this location right now. I'll post a couple when I come back for holidays and start on the bathroom. Thanks, again!
  20. pitterpat

    pitterpat HandyWOMAN

    Messages:
    46
    Location:
    Indianapolis
    John, have you attended a Schluter training course? If not then you should....also, why are you trying to keep people from being confused about using Kerdi when you are confused and have not attended a Schluter training course. Most of the people from the John Bridge Forum that post on this forum have been to the Schluter training course...even I have.

    Get with the Schluter rep in your area to see about going to a training course, they pay for you to stay there and take the course and you pay to get there. Then you will understand how to use the Schluter products and not provide confusing or incorrect info. http://www.schluter.com/media/BurnabyBC-2011-12.pdf
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