New Construction - Basement Slab Roughin

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by dondiy, Oct 10, 2007.

  1. dondiy

    dondiy New Member

    Oct 10, 2007
    I am building a 24' x 44' cabin. Plans have been approved, foundation walls have been poured and am roughing the plumbing in the basement before the slab is pour. The basement has 8 foot tall walls.

    There is a kitchen sink on first floor.
    Full bathroom on first floor (sink, shower, toilet).
    Full bathroom on second floor (sink, tub, toilet).
    Floor drain in basement.

    Each 3 set of fixtures is just above the stack individual stack in the basement.
    All 3 main stacks will be vented out the roof.

    Basement slab design (see attachment) is 3 stacks draining to basement, and a floor drain all emptying into a 4" pipe that leads to the septic tank. Cleanout just outside the foundation wall before septic tank.

    1)If all three stacks coming from the first floor are vented to the roof, do I still need an additional vent in the slab?

    2) Do I need a cleanout inside the basement if I have a cleanout just outside?

    3) To pressure test the system, do I just:
    a) plug the 3 stacks, floor drain, and connection to the septic line
    b)pressure the pipe with air
    c)assure no leaks for 15 minutes

    Thanks for your help
    Don DIY

    Attached Files:

  2. markts30

    markts30 Commercial Plumber

    Sep 25, 2006
    Commercial Plumber
    Phoenix, AZ
    1) If the floor drain is adequately vented, there shouold be no need for any additional vents (beyond the other floors that is)
    2)External cleanout should be good enough - include cleanouts in each fixture group as well - if there is a problem later you will be glad you did
    3)Yes you can use air - only use 5PSI though...
    We generally use a 10' head of water for underground testing (and above ground if there is no drywall up yet...)
  3. Sponsor

    Sponsor Paid Advertisement

  4. dondiy

    dondiy New Member

    Oct 10, 2007
    Drain Properly Vented?

    Thanks for the help.

    Just a couple of clarifications:

    1) Looking at the PDF, is the pipe layout correct? Does it make sense to connect all three stacks to a 3" pipe running down the center, or would it make more sense to run a main pipe diagnally from the furthest stack to the septic pipe to reduce pipe?

    1) Looking at the PDF, is the drain vent adequately vented? If not, where/how would I put the drain vent?

    Thanks again for you help.

Similar Threads: Construction Basement
Forum Title Date
Plumbing Forum, Professional & DIY Advice New home construction - failed plumbing rough inspection Tuesday at 7:09 PM
Plumbing Forum, Professional & DIY Advice Identify floor drain in new construction Sep 9, 2017
Plumbing Forum, Professional & DIY Advice Under Slab Plumbing - New Construction Jun 3, 2017
Plumbing Forum, Professional & DIY Advice New construction - water heater type/location May 27, 2017
Plumbing Forum, Professional & DIY Advice New Construction Plumbing Help Dec 7, 2016

Share This Page