How do you plumbers feel about wyes feeding into a horizontal drain line with the wye laying on it’s side rather than at 45 degrees or more? Is it legal? Is it bad practice? Is it done all the time?
Steve
How do you plumbers feel about wyes feeding into a horizontal drain line with the wye laying on it’s side rather than at 45 degrees or more? Is it legal? Is it bad practice? Is it done all the time?
Steve
Engineered-stone shower panels are waterproof, but proper installation relies on tight seams and silicone sealing.
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Replies
Mmoogie,
check with your local building codes, but here in MN you are only allowed to use a wye in a vertical stack. I had to rip out an installation when the inspector alerted me to this requirement.
Scott
Scott, I find that hard to believe. I think your inspector must be confusing the rules for a sanitary T.I just passed the licensing test for GC in MN. and they go by IRC, which allows the use of wye's horizontally. It would be virtually impossible to plumb much of anything without being able to tap into a horizontal branch line with a wye, at least with wye rolled up 90 degrees from the horizontal. My only question is whether it's allow with the wye on its side or not. IRC seems to say yes, according to the attached table.Steve
Hi Steve,I looked at my code book earlier and it appears that you should be fine. It matches what you've got in your table here. As a drain, it can be horizontal under UPC or IRC. As a vent it needs to be 45 deg.If you have room, you might be better with a combo than a wye, but I don't believe that's a necessity.And for the standard disclaimer, I'm not a plumber. Are you moving back to MN?Best,
Steve'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
Hi Steve,In the long run, maybe. My wife has been working out there for almost a year now. She went under the assumption I would be right behind her. She wasn't out the door but a moment when I got a call to do a whole house remodel that I've been working on landing for about eight years now. So It's looking like it's going to be awhile. But that is still the working plan. But you know what they say about plans...Steve
Illegal here.
Mike Hennessy
Pittsburgh, PA
Not sure about your specific situation but I do know that its better to have wye than a tee.
Check with your BI.
As far as I know, a T on its side is always illegal, as well as bad practice.Steve
You're right. You have to allow direction for the water. A "Y" is more likely to provide that (though not guarenteed to).
There are millions of wye fittings out there laying on their side. I'm not sure how you would plumb the drains in a single story house over a crawl (or SOG for that matter) without them... all those drains coming from the various rooms and needing to be tied together into one main drain leaving the house.
Now, when a wye or tee is used on its side as a VENT TAKEOFF it cannot be level... you have to rotate the side up at 45 degrees. Maybe that's the part that has you confused.
You can use a wye vertically. How else are you going to tie together two vertical lines? There's at least one gotcha related to using a wye or combo vertically if it's a trap arm inlet into a stack. Gotta use a tee there.
Or am I confused?
I ask because I just ripped out the drain setup that my plumber installed for a small bathroom I put together last fall. It's over a tight crawlspace, and he had the lav and the shower coming into the main horizontal via wye's on their side. I know I've read in various places that they should be rolled up at least 45 degrees. The most recent place being in Rex Cauldwell's (taunton press) book. In my re-working of the drain setup, I too found it impossible to get them up above horizontal very much, The shower now comes in maybe 10 degrees above horizontal, and the lav no more than a few degrees.I ran into another local plumber at lunch today and asked him if it was kosher. He said sure, as far as he knew. And this particular bathroom passed inspection (before I changed it) without a second glance. I could find nothing in the IRC that forbids it. In fact the attached table seems to say it's OK. I've no doubt it'll function fine, I was just wondering how pervasive the practice is.Steve
Edited 5/16/2008 10:43 pm by mmoogie
Maybe Plumbill will come along and hook us up...
I don't know of any code that prohibits a "wye" branch fitting on a horizontal plane to tie two drain or vent lines together.
Where codes vary is when the vent comes off the trap arm, almost all codes require the vent take off to be above the centerline of the horizontal waste line.
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