1st Floor Bathroom remodel

Discussion in 'Remodel Forum & Blog' started by K2, Oct 3, 2008.

  1. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley
    Hey guys, I'm getting ready to remodel the bathroom, i have it stripped down to the studs and subloor (which is 2x12 on top of 6x6 spaced 36").

    I'm going to tile the whole bathroom on top of a mortar bed. My question is what i have to consider with all of the rough plumbing for a toilet, shower, freestanding, bathtub and pedestal sink.

    Is it safe enough to assume I can just run the drains up high enough to clear the 'to-be' mortar bed and connect them after the tiling? Any special considerations for the toilet flange?

    I have access to the floor from underneath.

    Any thoughts are appreciated!
  2. Southern Man

    Southern Man DIY Hillbilly

    Messages:
    530
    Location:
    North Carolina
    Since this is an unusual configuration someone is bound to question deflection of the subfloor. I did anyway.

    A 2x12 subfloor on joists 36" will deflect under a 200# point load at L/1063. This assumes that the floor spans at least two joists. This exceeds the tile requirement of L/600.

    You could easily do a 1/2" cement board over the substrate and thin set tile instead of a thick mortar bed.
  3. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,262
    Location:
    New England
    If you use 4" for the toilet, you can cut it off flush after tiling then use an inside mount flange. Choose carefully as some don't have a square socket and the pipe needs to be below the finished floor level slightly for the flange to seat on top of the pipe and floor simultaneously - same thing on a 3" (an inside cutter works here). If you choose (or need to use) 3", then wrap something around the pipe so you have room to slide the flange over the outside. When tiling, it's easier to notch the tile before setting so you don't have to drill through , but it can be done after (might require a diamond bit, though- depends on the tile). If you want help with tiling, check out www.johnbridge.com site called Tile Your World.
  4. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,262
    Location:
    New England
    NO NO NO...never put cbu directly over dimmensional lumber on a floor. You need at least 1/2" ply, not for deflection in this case, but decoupling as the lumber moves too much with seasons!
  5. Southern Man

    Southern Man DIY Hillbilly

    Messages:
    530
    Location:
    North Carolina
    You may be right, but based on what he described it sounds like an ancient house, therefore very dry lumber and not likely to shrink/ swell. Of course he didn't state that so I could be completely wrong. Plus liquid nails between the CBU and the 2x12's would lock it all in place, no?
  6. frenchie

    frenchie Jack of all trades

    No. Seasonal variation in humidity'll still make the wood swell & shrink, if he glues the cbu there's no decoupling. crack city.
  7. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,032
    Location:
    Cave Creek, Arizona
    drains

    To do it correctly you should install the ENTIRE plumbing system then do the required water pressure test to be sure there are no leaks. THEN you can tile the room.
  8. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley
    Sweet, that makes sense, sounds like I can do the same for all my drains since I have access below it will be easy...

    When I ripped up the floor it was tile on 1/2" ply over the 2x12. Yes my house is 1945, don't know much about deflection but it sounds like my subfloor is pretty strong from the analysis? Most of the 2x12's touch at least 2 of the 6x6's. The 6x6's are sitting on top of 2 huge joists that run the length of the basement with 2 column supports on each run. The joists are 6 2x12's nailed together standing on ends.

    I thought a picture would be helpful to assist me in my plumbing...I'm not familiar with all the right terms (pretty sure I got the toilet right...)but the guy at my local plumbing supply store helped me configure this diagram:
    [​IMG]
    I currently have a cast iron stack from basement to 1st floor and I replaced the 1st floor to roof with ABS.
    The picture is what I want to do next. The tub/shower/toilet are all on the same floor i just can't draw 3D yet :)
    does anyone see anything bad with this setup? (the shower & tub will have traps, didn't draw them)
    The black is straight ABS 4 and 2 inch. All fittings should be labeled...
    thanks again for the replies!
    Last edited: Oct 4, 2008
  9. Redwood

    Redwood Master Plumber

    Messages:
    7,450
    Location:
    Connecticut
    Toilet an shower enter the stack on a 4 X 4 X 2 Sani-tee?:confused:

    Tub and shower need proper venting.

    Where is the lav sink?

    Did you buy a PEX tool yet or, is my sharkbite stock going to pay another dividend?
  10. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley

    The lav sink is drained & vented on the other side of the room on a different line.

    Sorry that's supposed to be a 4x4x4 Sani-tee (copy paste error), would that make it less confusing?

    How do I properly vent the shower and tub? The tub drain is less than 14" from the main soil stack can't that be the drain/vent?

    The 4x4x2 sloping tee in the diagram is supposed to be the appropriate vent for the shower (he told me any fixture over 42 inches from the main stack requires a vent on the way) is that not correct venting for the toilet and shower?

    i'd say hold on to that sharkbite stock for the immediate future ;)
    Thanks!
  11. Southern Man

    Southern Man DIY Hillbilly

    Messages:
    530
    Location:
    North Carolina
    Nice drawing.
  12. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley
    Thanks!

    I still have a couple questions about this setup:

    1) How can the Tub be properly vented, if the tub is 1 foot from the main stack can I use this as the vent as shown in the diagram?
    2) Can I use the sloping tee as the vent connecting to the main stack to vent the toilet and shower?
    3) Is the double wye used correctly in this diagram?
  13. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley
    Ok, read a lot on John Bridge forum, how about osb sleepers, sand for thermal mass to fill the spaces, cement board over the osb, then a ditra layer for tiling?

    i'm contemplating mudding the whole first floor...seems like the industry standard.
  14. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,262
    Location:
    New England
    Mud is a great surface to tile on and provides a flat surface and good thermal mass, but it is very heavy. Your structure may not be designed for it. It's a lot of work carrying, mixing, and laying it down - not all that hard technically once you get the hang of it, but physically tough.

    Ditra is really neat stuff and is a good choice over a heated floor as it provides exceptional decoupling with minimal insulation. If needed, you can seal the seams and end up with a waterproof floor, too (but it isn't needed that often). Ceramic tile can live with one layer of ply, but if you decide to go with a stone, you must have two layers of ply, properly installed.

    From ease of install, a staple up system with the aluminum channels/heat diffuser panels would be easier and almost as good. As long as you've got insulation so you don't lose much below, it can be good and responds faster. So, lots of ways it can be done...
  15. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley

    yeah tons of different ways, almost too many! Not to turn this into a radiant forum but what about WEDI board as the sleepers, with self leveling concrete to fill the gaps and provide rigidity then ditra that and tile/hardwoods?

    easier? quicker? cheaper? less rise from subfloor? more efficient?
  16. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,262
    Location:
    New England
    Wedi is made of of foam with a proprietary coating that enables thinset to stick to it...it's a decent insulator and waterproof. Probably not what you want since it would not be a good heat diffuser. It's a nice product, but expensive. If it fits your needs, it can be cheap, but I don't think this is one of them.
  17. Radiant heat? (Did I miss something?) Are your joists bare? Did you cover them with plywood?

    In your first post you said
    If you want comments on Wedi, say what it is resting on.

    David
  18. K2

    K2 New Member

    Messages:
    77
    Location:
    Delridge Valley
    David not sure what you're asking?

    My subfloor is 2x12, which is on top of 6x6, on top of 2 main joists which are made up of 2x12 on end.

    I was considering using WEDI as the sleepers for radiant tubing instead of OSB. The wedi would be on top of the 2x12 planks that are my subfloor and the radiant tubes would be between cut lengths of WEDI.

    This post was supposed to be focused on my bathroom remodel (see pic) specifically, it's deviated from that...
  19. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,262
    Location:
    New England
    Wedi can't be attached directly to planks, so you'd still need a layer of ply. As I mentioned, I don't think the insulation properties of Wedi would benefit your radiant heat installation...
  20. Retablo

    Retablo New Member

    Messages:
    19
    Location:
    NYC
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