I am in the midst of a remodel and have a question about plumbing the waste lines for a new bathroom. The new bath is on the other side of a common wall with an old bath that will be reconfigured in the (hopefully) near future. My main sewer line lies just below the existing bath, and has a seperate tap for the toilet, shower, and sink into a horizontal 4″ sched 40. When I redo the existing bath, all the fixtures will move. My question is, can I hook my new shower and sink lines (2″ and 1.5″) into the existing taps for the same fixtures for the time being. For example, my old shower is on a 4X4X2 tee, and I would like to pop my new drain into the 2″ line, rather than adding a new 4X4X2 to the main line. The new shower drain line would have to come in above the trap for the existing shower.
I cannot foresee both showers running at the same time, and I doubt I have enough water volume to overwhelm the 2″ drain anyway. Am I asking for trouble? It would make my life much easier, we have a household of 6 and trying to find the time drop the whole line would be really difficult right now. Thanks in advance.
Replies
The reason we have building codes is because your usage may be OK but the family you sell to will cause problems. Example--one bath may not need an anti-scald valve but two will.
There are specific distances you can run with certain sized pipe before vents or reventing is required.
Get a licensed plumber, read the code or draw out what changes you want to make and when you get your permit ask to review your plans with a plumbing inspector (a carpenter inspector won't educate you much).
PS You may be doing the work and the house may currently belong to you but a permit is still necessary and an inspection comes with it.
When you want to sell the house and the prospective buyer has it professionally inspected (required for a loan) you will be money ahead to have done it right and get a good report.
Otherwise you'll have to tear out the cluster**** you seem to describe (could involve concrete board, tile, studs, floor covering, paint).
Tyr
Tyr,
Thanks for your response, but things are less/and more complicated than you want to make it. I have asked 2 local plumbers and gotten different answers (thats why I posted here). I live in a small, rural community and there is no permit, no building inspector or code enforced locally. Your profile says Denver area, I am in very rural Nebraska. I could find the code info if I spent enough time, but I trust most of what I gleen from the folks on this forum. I have a fair amount of construction experience, but can't recall seeing what I have asked about.
Bottom line is that regardless of what I do now, it is not permanent. The existing bath has to be redone, and with a graduation next May, likely will be sooner than later. There is full access to the old plumbing via an unfinished basement, but the existing fittings are too close together to easily fit in new additional fittings now. "yes, go ahead", or "no, don't because" would help tons. I have to have a 2nd functional bathroom very soon.
Check your private mailThings are not always what they seem; the first appearance deceives many; the intelligence of a few perceives what has been carefully hidden.... Roman Poet Phaedrus 15BC–50AD
Tell her your going to wait and do this right, rather than redo it two or three times.
Would love too, but its not an option. I have to have another functioning toilet in the next couple weeks, and though it is plumbed into the same 4" waste line a bit further down, it would make life much easier it I could turn on the valves to the sink, shower, toilet and washing machine at the same time. I had hoped that I could plumb in the waste lines for the shower and sink as proposed, then when I move the fixtures in the old bathroom, I could cut out the tees that feed those fixtures and repipe the drains for the 2nd bath directly in via the stub of the old drains (there is enough "stub" left up from the 4" to allow this). That would then leave a clean, neat hook up. Otherwise, I have to cut the main, add 2 more tees now, then when I do redo the old bath, abandon those that feed the old fixtures, and add more tees to feed their new locations. In fact, I would probably wind up pulling the whole run and redoing all drains just to avoid a cobbled up mess.
So my question remains, can I run a 2" drain into another 2" drain, then to the 4"main, and a 1.5 into a 1.5" and into the 4" main, or do I wind up plumbing in new tees and abandoning old tees multiple times?
Your temporary fix will work just fine.
You are right to suppose that both showers running at the same time will not overload the 2" drain line. Shower valves only flow 1-1/2 gal/min and a 2" horizontal drain will easily handle two of these. Toilets and sinks and sinks will be fine, too.
When the time comes to do it right, you will still have access (it seems you must have a crawl space?) to the lines to tie things in separately.
There may be rare occasions when one or the other of the traps will burp because of not being vented individually, but this is a small price to pay for dealing with the urgency of your current problem.
The sink drain you should be able to tie in permanently, and to code, by cutting in a sanitary tee (not a wye) in the vertical drain line that now serves the existing sink--cut the new tee in immediately below the existing tee, and run the trap arm with 1/4" per foot slope--don't jump it up to make it come out of the wall higher; this would create an S-trap that will self-siphon the trap. Just use a longer tailpiece to drop from the sink to the p-trap.
The sanitary tee for the sink drain could also be cut into the vertical vent for the existing toilet, if that's handier. Doing the sink correctly now will make it so you don't have to mess with your finished walls later--all code-compliant work will be done in the crawl space.