1-1/2" Lav PVC piping. Short 90s throughout

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I'm plumbing a lavatory sink. I'm using 1-1/2" piping from a floor above. I have to bypass a floor beam so I went through the wall studs. I drilled through the studs and pitched the pipe 1/4" per foot slope. After passing the location of the beam (about 7' run) I went down through the floor to the level below using a 90 elbow (Not long elbow, the short elbow). I then used another 90 deg. (down about 11 inches in the 2x12 joist bay) going from vertical to horizontal traveling about 4 feet, then another 90 deg through the joist going horizontal to horizontal then connected the pipe to the main drain about 2 feet from the last elbow.
My question is, since it's a lav, would it be permitted to use those 3 90s without being long turn? I already glued the pipes but I guess I can take them out if I have to, the drywall is out now. I wanted to have some opinions about this before I call the plumbing inspector. I'd rather not fail the inspection...
 

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Reach4

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I expect NYC code is seldom more tolerant than UPC and IPC, and those would not be allowed by UPC and IPC.
 

wwhitney

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I expect NYC code is seldom more tolerant than UPC and IPC, and those would not be allowed by UPC and IPC.
Per Table 706.3 footnote a, the IPC allows a quarter bend to be used for all changes of direction for a 1-1/2" or 2" fixture drain (drain carrying only one fixture).


Cheers, Wayne
 

Reach4

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Suppose that lavatory drain line is used to wet vent something?
 
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I expect NYC code is seldom more tolerant than UPC and IPC, and those would not be allowed by UPC and IPC.
I've had my fair share of arguments with building/electrical inspectors who had not even heard of common sense and I've learned to always avoid the hassle of arguments. I now try to go above and beyond to make sure I won't be asking for favors. Also the veteran seasoned inspector who used to side with me against the jerk just quit late last year and I'm now facing to deal with the jerk solo... Today I decided to scrap what I did and I redid the pipe and eliminated all the short bends. Better safe than annoyed.
 
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Suppose that lavatory drain line is used to wet vent something?
The reason for all the hassle is that there is a structural beam in the middle of the bathroom between the lav and the shower/WC. I could've went through the floor and sloped in a joist bay but I would've had to cut through the beam and hack the heck out of it in order to meet with the shower/ WC in a traditional wet vent setup but I never give plumbing or any other mechanical priority over structure. For this reason I ran the pipe in the wall over the beam then down to the other side to meet up with the rest. I also prefered to have the lav as the only fixture in order to use 1-1/2" vent instead of any larger 2" vent piping that would weaken if not completely devastate 2x4 studs.
 
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Per Table 706.3 footnote a, the IPC allows a quarter bend to be used for all changes of direction for a 1-1/2" or 2" fixture drain (drain carrying only one fixture).


Cheers, Wayne
Earlier today I contemplated having to deal with a clog in the pipe, it's a rare situation but it does happen, hair or anything else thrown in the sink can possibly go past the trap and be lodged in one of those quarter bends. At first I thought of installing a cleanout but it would be only accessible from the outside face of the bathroom wall and being that the outside face would be the bedroom that's when I decided to scrap the quarter bends and go with with 1/8 bends instead.
I will post photos shortly
Thanks for your input.
 
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Here are the photos:
I had to come up with a way to cut the floor at 45 deg with a hole saw so I used a piece of 2x4 to replace the one between the last 2 studs which had to be removed in order not to end up with a hole in the floor. I then cut a piece of 1-1/2" PVC as a 45 deg and used it to gauge where the pipe would travel. I also cust a piece of 2x6 wood at 45 deg and used it to gued the drill at perfectly 45 deg. which wasn't easy because of having to drill with a hole saw blade at 45 deg angle. But it was done and I replace the floor plate with a new plate between the studs then ran the pipe with 2 1/8 bends. I also used on long turn quarter bed at the last 90 location right after the second 45.
When there's a will there's always torture...
 

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I'm not aware of any interaction between IPC Table 706.3 and Chapter 9 on venting, so I don't believe that matters.

Cheers, Wayne
Reach4 didn't comment in reply to your IPC table, he/she was trying to fail me hypothetically. If he/she were a plumbing inspector they'd not only fail me with information given but also with hypotheticals. He/she were insinuating that the sizing is also incorrect.
 
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On your photos, are your holes in the joists all 2" clear from the top of the joist?


Cheers, Wayne
2" is always the starting point then sloping from there when drilling through conventional lumber. Engineered lumber is a different install. Obviously you know why because you're asking... As I said in a previous post, I never give priority to anything over structure.
Thanks Wayne
 
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Yea I give structural integrity the highest respect, in fact even if I encounter a shiner I go out of my way to pull the nail out for aesthetical purposes (an example would be making the unused drilled hole in the floor for the removed 1-1/2" pipe disappear)..
 

Tuttles Revenge

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Long sweeps are required for all changes in direction from Horizontal to Horizontal and Vertical to Horizontal. Where the 90 in the stud bay transitioning from Horizontal to Vertical was perfectly fine.

The exception 706.3 only applies to Fixture Drains, which is the elbow between the vent and the trap only.

And judging from the use of the terms 1/4 bend, short sweep and long sweep. Those are terms used for cast iron fittings.
 

wwhitney

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The exception 706.3 only applies to Fixture Drains, which is the elbow between the vent and the trap only.
No, that would be the trap arm. The definition in Section 202 of the IPC:

"FIXTURE DRAIN. The drain from the trap of a fixture to a junction with any other drain pipe."

So the fixture drain extends past any dry vent takeoff to the first junction with another drain pipe. Obviously for wet venting, the fixture drain and the trap arm are the same.

Cheers, Wayne
 
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Exactly a scenario where an argument as I mentioned, occurs with an inspector, this is why I opted to just kill all chances of arguments and go with the 1/8 bends. Not worth getting upset over it or getting fumed over being red tagged. BTW, based on medical research only 8 minutes of anger reduces capacity of blood vessels lasting over 40 minutes. That's why older people with weak circulation to begin with are at risk of a heart attack because of anger episodes. Not there yet but why ruin your day... Besides the flow is better this way and no need for cleanouts.
 
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Jeff H Young

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1/4 bend on side never had a legit use besides vents aboove flood level in my practice or observation of other plumbing work. Only legit exception was a pedestal lav or somewhere a long sweep was unsightly. some guys put looks befor function For example drill out studs under a window for a trap arm vs run exposed behind cabinet , I go for the latter with a 1/8 bend on side toward a kitchen sink someguys probeblly use a 1/4 bend on the side for good looks and make a few bucks down the road on drain cleaning LOL
 

Tuttles Revenge

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Another weird thing that the IPC allows. But as in almost all cases in the code, these are the minimum requirements and the OP here is going above and beyond the minimum to minimize his exposure to clogs and inspector hassles.

Fixture Drain is a term that doesn't come up very often and my reading of it I interpreted it as synonymous as trap arm from the way its used in other text. Something I'll have to look up and see if they're the same in UPC and if that gives me any wiggle room in our projects.
 
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1/4 bend on side never had a legit use besides vents aboove flood level in my practice or observation of other plumbing work. Only legit exception was a pedestal lav or somewhere a long sweep was unsightly. some guys put looks befor function For example drill out studs under a window for a trap arm vs run exposed behind cabinet , I go for the latter with a 1/8 bend on side toward a kitchen sink someguys probeblly use a 1/4 bend on the side for good looks and make a few bucks down the road on drain cleaning LOL
So you're basically saying that this has no purpose...
 

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