Supply line design and size for 2nd bathroom

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Sterling, Jan 3, 2008.

  1. Sterling

    Sterling New Member

    Messages:
    6
    Location:
    Alberta
    I am adding a new bathroom in my basement directly below the main floor bathroom. After looking at Terry's chart on supply line sizes, it looks like branching off the main floor bathroom's 1/2" lines will lead to problems. I'm wondering if my supply system will properly support the new bathroom (toilet, lav, shower w/ body jets).

    I have 3/4" leaving my water meter which then feeds (in order): clothes washer, 2 hose bibs, 1/2" line to main floor bath/shower lav toilet. Then the 3/4' reduces to 1/2" which feeds the hot water tank, and then the kitchen sink/dishwasher.

    The hot water then feeds (in order): kitchen sink/dishwasher, clothes washer, main floor tub/shower, lav.

    I was going to just tap off the 1/2" lines going to the main floor bathroom to feed the new bathroom but now I'm wondering if I should run a new 1/2" back to the 3/4" supply instead. I don't see much alternative but to run the hot water off the existing supply.

    Any advice or comments would really be appreciated.
  2. therinnaiguy

    therinnaiguy New Member

    Messages:
    20
    Location:
    Massachusetts
    Home run it

    Check out the new plastic (PEX actually) water lines. They are easier to use, have less elbows for greater flow, are a good DIY'er project and cost way less than copper. Run a 1/2" line from your water main and as close to the water heater as you can to each new fixture. This way you will not get scalded if someone flushes the toilet. So for example you will have 3 cold water lines and 2 hot water lines for a tub/shower combo, Lav and toilet. 5 lines will still cost you less than by doing a 3/4" copper cold and hot water supply.
  3. Sterling

    Sterling New Member

    Messages:
    6
    Location:
    Alberta
    Thanks for the input. Just so I understand, I should run 3 separate lines from the 3/4" supply and 2 separate lines from the hot water supply line close to the HW tank? Sound right?
Similar Threads: Supply line
Forum Title Date
Plumbing Forum, Professional & DIY Advice Flexible supply line for clawfoot tub Oct 2, 2014
Plumbing Forum, Professional & DIY Advice Would old supply line cause low pressure? Jul 2, 2014
Plumbing Forum, Professional & DIY Advice Next steps before replacing hot supply line Jul 1, 2014
Plumbing Forum, Professional & DIY Advice Bathroom drain and supply Lines Jun 22, 2014
Plumbing Forum, Professional & DIY Advice Bathroom vanity supply lines under vanity? May 9, 2014

Share This Page