(206) 949-5683, Top Rated Plumber, Seattle
Page 1 of 4 1234 LastLast
Results 1 to 15 of 46

Thread: Big basement bathroom project

  1. #1

    Default Big basement bathroom project

    I have a narrow basement. The bathroom currently sits square in the middle wasting space for what could be a very usable room. Meanwhile, I have wasted space at the other end of the basement where I want to put the bathroom instead (where the washer and dryer are).

    I have included two rough diagrams (not to scale)

    The existing 3" flloor/vent stack/sewer line are shown. A 2" vent will cross the ceiling for 10' and then turn and travel 8' to the existing 3" vent stack. It will be attached to the vent stack above the highest drain connection.

    For the vent stacks servicing the new bathroom, do I need to put a third for the toilet or will the two branches serving the sink and tub be sufficient?

    The existing sewer line is 2 1/2' below the foundation. The new run will drop 4" over the 16' run. It won't connect to the floor drain as it appears in the rough diagram. That drain is actually offset from the sewer line.

    My big concern is the 90 deg in the sewer for the new bathroom. Is this acceptable? Is there a better solution to turn that corner?


    Last edited by fiasco; 11-14-2005 at 12:59 AM.

  2. #2
    Plumber Cass's Avatar
    Join Date
    Nov 2005
    Location
    Ohio
    Posts
    5,984

    Default

    As far as the 90 goes bust up more of the floor and use 2 - 45s with at least 2' of pipe between them. When you say "The existing sewer line is 2 1/2' below the foundation." do you mean the floor or the footer can you be more specific?

  3. #3
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,671

    Default pipes

    A plumber would simplify the layout by using a long radius elbow at the turn and also below the toilet connection, then he would use a 3x2 side inlet tee for the toilet and bathtub/shower with the 2" going to the P trap. Then the lavatory/sink would connect to a T in the toilet's 2" vent line and then the single vent would connect back to the 3" above all the other connections, which means it would be at least 42" above the floor in the first floor wall. You would also need a 3" cleanout in the pipe above the floor behind the toilet.

  4. #4
    In the Trades Bob NH's Avatar
    Join Date
    Oct 2005
    Location
    New Hampshire
    Posts
    3,307

    Default

    You will save about 4 ft of breaking concrete if you run the sewer line diagonally.

  5. #5

    Default

    Cass,

    I was planning on using two 45's to soften that elbow. i wish I could go diagonaly but that would require moving the furnace. The sewer pipe is 2 1/2' below the top of the floor.

    HJ,

    I gather from your description that something like what is in the attached image will be ok?
    Attached Images Attached Images  

  6. #6

    Default

    Or, would this be acceptable? This would be easiest because it' will be difficult to get the new 2" vent line coming out of the floor close to the wall. I'd be able to hide it more effectively behind the tub installation.
    Attached Images Attached Images  

  7. #7
    Plumber Cass's Avatar
    Join Date
    Nov 2005
    Location
    Ohio
    Posts
    5,984

    Default

    I hope you mean 2 1/2" from the bottom of the floor because most floors are 4" thick. Even still unless I'm not getting something right where you make your tie in the existing line will be higher than where the run ends. Am I not understanding you right? If I do get you right you will need an ejection pump and pit.
    Last edited by Cass; 11-14-2005 at 01:12 PM.

  8. #8

    Default

    The sewer drain is approximately 2 1/2' (feet) below the top of the floor where it exits the house and that is where I will be tieing in.

    is the vent pipe diagram I last posted acceptable?

    Lastly, when I repour the cement I don't want the slab settling. Can I drill pilot holes in my cut edges and insert some short rebar (spelling?) to support the new cement?

    I'm still in demo mode right now. I have most of the trenches cut in the foundation and have broken up the cement and carted it away. I'll be posting pictures of my bathroom project as I progress. Home demo is always tough because I have to account for the WAF (wife acceptance factor)!

    I do truly appreciate all of your advice!
    Last edited by fiasco; 11-14-2005 at 05:59 PM.

  9. #9

    Thumbs up

    OK found an answer to my rebar question and pilot holes for rebar dowels.

  10. #10
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,671

    Default

    Quote Originally Posted by fiasco
    Or, would this be acceptable? This would be easiest because it' will be difficult to get the new 2" vent line coming out of the floor close to the wall. I'd be able to hide it more effectively behind the tub installation.
    Its going to have to be "close to the wall" somewhere, why would it be difficult behind the toilet? That drawing makes the lavatory arm too long. I don't want to take the time to do a new drawing, but if I were doing it, the tee would be in the floor under the new wall behind the toilet, and the tub would go into the side of it with the toilet's closet bend into the 3" opening. Then the vent would go vertical with the tee for the lavatory at the proper height, then a 3" cleanout about 36" above the floor with a 2" bushing in the top of it. There are a few of "good" ways to install your layout, and hundreds of "bad" ways that look easier. Your job is to separate them and pick the best one for you.

  11. #11

    Default

    HJ,

    Again, I really appreciate the input. I am still in demo mode, got to move the washer dryer, water softener and water heater so I can get to the existing sewer run.

    I just installed Visio so I will post some actual plans instead of stick drawings probably later tonight.

  12. #12

    Default

    Rebar dowels are probably a bit overkill for a basement floor. Compact the dirt well when back filling.

    When we use rebar dowels in larger commercial applications, we epoxy one end in the existing slab and grease the other so it does not adhere.

    Paul

  13. #13
    Plumber/Gasfitter dubldare's Avatar
    Join Date
    Sep 2005
    Location
    MN/ND
    Posts
    286

    Default

    Here's how I'd do it.
    Attached Images Attached Images  

  14. #14

    Default

    Here is the floorplan layout. I'll post plumbing diagrams later tonight.


  15. #15

    Default

    Is there a specific "schedule" PVC pipe that must be used for DWV?

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •