Running 3″ Drain pipe
In my bathroom relocation I have to change the direction of the 3″abs drain pipe. The pipe starts at the toilet, after approx. 3 feet of horizontal run a 2″ shower drain is connected with a Y-piece. Then after another 4 feet of horizontal run I want to put a 90 elbow pointing downwards. Right after this I want to put another 90 elbow going to the left side. Then there is a 5 feet horizontal run before it finally connects to the drain stack that disappears in the basement floor. Is this going to work or will I get problems at the two 90 turns?
Is this drain going to be covered over? if so you will sooner or later need to tear it out to unplug the drain. % feet of horizontal will slow down the water flow right after the two 90 degree turns..
Not saying that it's not done just that such an arangement will sooner or later be plugged up..
It is not exactly horizontal, the pipe will have the required 1/4 " pitch. And it is going to be boxed into a sofit-box under the kitchen ceiling. I like the idea with the 45 turns.
Think like a turd,
the water will carry out easily with just a 1/4 inch per foot but will the turd? the two tight bends will slow it down and then the turd will have to carry 5 feet almost flat by the time it gets past those 5 feet the water will be gone and the turd will stick..
a few stuck turds and suddenly you have a mess to clean out..
those big sweeping bends are much better than a two tight 45's, but the flat section is the real problem.
I have a similar situation in my house but it's under the kitchen sink.. accordingly I put cleanout plugs in both ends of the flat section and expect that when the inevitable blockage happens I can unscrew the panels under the pipes and get a snake into the cleanout plugs and unstick the problem..
Where your design is forced to compromise, think in advance and deal with the problem.. Don't cover it up and hope it won't happen.
What about this idea: after the 6 feet horizontal run from the toilet I put a 45 pointing to the left side at a 45 degree angle. Then I run a pipe downwards at a 45 degree angle before it feeds in the main downpipe. In this case I only have one 45 bend and the solids can run down in the 45 degree angled pipe. What do you think?
You should not have any problems with the 45s'. Maybe, not even the 90s'.
Frenchy's turd analogy may or may not be correct. Water out running the solids has been debated here a few times.
My experience in a commercial office building is that it isn't the poop that clogs the waste lines, it is the paper. Most of our horizontal runs are longer than what you plan, but we have a few that short or shorter. The vertical drops are all 90s' and are on average 15' before transitioning to another horizontal run. This is a three story building that is a city block long, and has over 500 people in it daily.
99 to 99.9% of the time the blockages we have to clear are caused by (1) excessicve use of toilet paper, (2) paper towels in addtion to tp, (3), cloth in the form of dicarded undies, and (4) assorted other forgien solid objects.
Check with your local plumbing inspector for his recommendations on your design. the phone call and advice are free.
If you do put in cleanouts, keep them on the top half of the pipe, and away from any transition points that cause turbulance in the stream flow. Do not use directional tees for cleanout locations. They limit the direction you can send the snake if you do get a blockage.
If I were you Ide forget the 90's , or if you absolutely need them use long sweep 90. The idea is to not have any restrictions in the drain, some 45's might also be a better way to go?
Why do you need so many turns? is there any way to use a Y instead of turning the drain, make two drains run into one.
Just a thought?
I am afraid We just don't have enough details to know what is really going on.
Good luck on your project.
You will have problems with two 90's unless you only pee in this toilet.
Have a good day , eat some cheese!
Do you have any better ideas? Any help is appreciated
rule of thumb my plumber told me. never go over a total of 360 degrees by adding up all the bend from toliet to tank
I am trying to imagine or sketch your situation. The 2 inch from the shower is your wet vent. The only suggestion I have that may work is instead of 2 90's close together, can you use 3 45's with short pieces of pipe to get the drain line going in the right direction? With the high water flow of the shower and toilet the line should flush pretty well. One of my bathrooms has 2 90's close together near a vertical stack and I find that the most sluggish toilet in our house. I've been meaning to go in the basement and make a couple changes as it is right above my utility room but I just don't seem to have time. There are too many jobs to do and not enough hours in a day.
Have a good day
Curtis is basiclally right. Use long turn ells or 45 degree fittings. If you have any place where you can install a clean-out on the horozotal Line, do that. If you can't, don't worry about it. What clogs up sewer and waste lines is not turds, but people that think they are trash cans. The pitch of the line is more than enought, Good luck!
Can you plumb the whole run from the toilet to the main vertical drain stack in 4" pipe ? That would be a cheap insurance policy.
Yes I could probably run a 4" pipe and not of a 3". Would it make a big difference?
First, I should have said that I was assuming your main drain stack was 4". (If it isn't, you can do this). I'm not a plumber, but in my personal experience, stoppages in 3" pipe are 10 times more common than in 4" pipe. Hopefully others will have opinions.
Nope, the main stack is 3".
I don't think the plumbing codes allow you to decrease the diameter of the drain pipe in the direction of the flow. Of course, if the sewer line coming up out of the basement floor is 4", and if it's just a short run of vertical pipe from there to where you are tying in, you could just make that 4" all the way.
As I said, hopefully others will have opinions about the frequency of stoppages in 4" vrs 3"
but there would be more water in the bottom of a 3 than there would a 4