Does every P-trap require a separate vent pipe or are there conditions where one vent can serve two P-traps?
Example 1: 3″ main starts with a toilet, then a 2″ vent and a separate 2″ shower drain ties in. Toilet to shower about 3½’.
Example 2: 2″ shower, 2″ vent, 1½” tub, then ties into a 3″ main. Shower to tub distance about 5′.
Engineered-stone shower panels are waterproof, but proper installation relies on tight seams and silicone sealing.
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Replies
in most cases you can vent a whole house here on one vent... the placement in line order is the issue... you can run 5ft from the stack before you have to come back and over with another vent... the whole idea is so that a huge rush of waste can't suck another trap dry...
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That "5 ft" depends on the size of the drain and which code he is under. Of course there can be local modifications on top of that.And also how much wet venting can done depends on which of the two major codes (UPC or IPC/IRC) is being used.Seem in plumbing codes there are a much wider variation than in other codes.This has similar information to the other link, but covers both codes and has more of the tables filled in.http://www.codecheck.com/pg13_14plumbing.html#drains
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
shower, tub, sink, floor drain, washing machine, need p traps. toliet has built in p trap. I have all of my whole house on one vent, its a 4 inch vent but legal. anything within arm length tie to one and then above ceiling height. then tie all those together to one exit through roof. have some fall included.
I understand that all the vents can tie together before penetrating the roof. What about the number of places the vent ties into the drain line near the P-trap or toilet? Can one vent tie-in to the drain line be shared by two p-traps if within X-distance?
Here is a website that explains a lot. There's a section on vent configuration. Good luck! http://www.masterplumber.com/Laws/UPCExcerpts.html#toolow
I got four on one. three on another, and two on another then all goes into a 4 inch going out roof.1)sink, shower, toilet,washing machine
2) toilet, sink, shower
3)kitchen sink, dishwasher
I'm far from being a plumber but I've never seen a 4" stack on a single family home.
Code states the cross sectional area of the vent shall equal the cross sectional area of the waste going out.
I prefer to do a single 4" vent verses a bunch of smaller ones, sure it's more piping, but less chances for a roof penitration to leak.“How many observe Christ’s birthday! How few, his precepts! O! ‘tis easier to keep Holidays than Commandments.” —Benjamin Franklin
Code in NC (2000 IBC) allows a single 2" vent to vent the entire house assuming air admittance valves used as needed. The issue here is every trap needs to be properly vented and this is not always possible without multiple vent stacks or air admittance valves. Sometimes it's worth calling a plumber.
I live in NC too... I probably need to get myself a code book. Do you know if the 2006 plumbing code (based on IPC 2003) has been adopted? I know the building code is held up by some kind of political BS.
BTW - if you don't mind me asking, what area of NC do you live in?
I'm in Saxapahaw, near Chapel Hill. The new IRC goes into effect today but the books are hard to get. I ordered two @ $75 each back in November and they haven't come yet. Our annual plumbing comntinuing ed class ran us through the changes, biggest one for us is washing machine waste switches from 2" to 3" when the stack goes horizontal under the floor. And venting gets a LOT more flexible.
Saxapahaw?? I had to look it up on mapquest... I've ridden motorcycles through that area several times...
>> washing machine waste switches from 2" to 3" when the stack goes horizontal under the floor. And venting gets a LOT more flexible. << That is real interesting... Sounds like you are a plumber. Any more specific info like that would be very welcome. BTW - I live in Apex - just south of Raleigh, but mostly work in Raleigh. I found this link for a book: http://www.constructionbook.com/xq/ASP/ProductID.6402/id.377/subID.629/qx/default2.htm Did you order yours from the code place in Garner, or some kind of regular commercial book source?
Thanks,Matt
Yeah, I'm a plumber but also a builder and a radiant heat guy. I ordered my book from Mechanical Contractors of NC. Still haven't received it so your link sounds good, that is the correct book. MCNC gives good code review classes that focus on the updates every year and I like to go through and highlight and mark up my code books.
Yes you can have one vent serving more than one "P" trap.
It is quite common & we do it all the time for back to back plumbing fixtures when we use a "cross" fitting that has two trap arms going into a single stack.
“How many observe Christ’s birthday! How few, his precepts! O! ‘tis easier to keep Holidays than Commandments.” —Benjamin Franklin