Trap Arm or Obstruction issue?

[Tuttles Revenge]

We moved a toilet trap arm location a few inches in order to change the direction of the toilet for new layout. Removed an existing lead bend and banded onto the lead bend / brass ferrule with a 4x3 reducing band. 3" pipe to a 3x4 manufactured closet bend.

What we modified

The correction notice and the applicable UPC/SPC 1003.3 cited and what I think the inspector was obviously missing UPC/SPC 310.5

Am I missing something?

 

[John Gayewski]

The ferrule and lead part is what I'm thinking. How can you connect to a lead pipe without stiffening it from the inside of the pipe, which would restrict the flow and cause snags.

I'm not clear on this system or how you connected these pipes. How does this ferrule work?

 

[Sponsor]

 

[wwhitney]

Seems like implicitly 1003.3 only applies to fixtures with field-installed traps. And 1003.3 doesn't explicitly say you can't enlarge the WC fixture drain from 3" to 4" before the vent, which I assume is the issue the inspector is concerned about.

Cheers, Wayne

 

[Terry]

Since you have 3" going into a 4" hub was he hoping for a 4x3 closet flange?

 

[Jeff H Young]

can't read correction notice so can't guess what you were written up for.
I wonder if its about you reducing the trap arm from 4 inches at the san tee to 3 inch I don't see anything wrong with it unless the ID on the connection is smaller than your 3 inch ABS if that's the case and the ID drops bellow that of the ABS then there would be a problem

 

[Tuttles Revenge]

cant read correction notice

The correction says "1. Provide toilet trap arm in main house without a reduction in pipe size in accordance with 1003.3 of SPC"
Seattle Plumbing Code.

 

[Tuttles Revenge]

The ferrule and lead part is what I'm thinking. How can you connect to a lead pipe without stiffening it from the inside of the pipe,

A lead ferrule is basically a heavy brass insert (copper dwv sized) that the lead would be wiped around and sold with the elbow ready to go (typically at the Bunker Hill lead factory, I have a copy of the catalog here) and inserted into the san tee. Our clamp is either on the lead / ferrule or on the ferrule directly. Both is typical of remodel work in the area and way better than the sewer fernco that most hacks (done it myself back in the day) use most of the time.

We're connecting a 4x3 closet bend to a 3" trap arm which is connected to a 4" tee.. the only reduction is the closet bend, which is explicitly allowed in the UPC/SPC code. After that fitting the pipe sizes only increase.

 

[wwhitney]

It does sound like the inspector is calling out the 3x4 reducing closet bend. I don't think the code citation is on point. But perhaps you need to ask the inspector what he/she means, and if it is just the 3x4 reducing closet bend, get a definitive opinion from a higher up.

Cheers, Wayne

 

[Tuttles Revenge]

But perhaps you need to ask the inspector

I spent an hour attempting to call the inspector this morning while they're in the office for the purpose of talking to plumbers. They sequester themselves so well against talking to plumbers!

 

[Terry]

Reminds me of an inspector that wanted me to install a 1.5" cast iron pipe for a vent one time. Said it was an oversized vent.
I had run it with 2", my normal way.
When I asked the head inspector why that could be a problem, he laughed and said it wasn't a problem.

 

[Tuttles Revenge]

Inspector called me back. I still believe that his interpretation is incorrect. He said that the san tee is 4" and that using a 4x3 reducing fitting is an obstruction.. saying we reduced the size. However, after not being able to convince him that his interpretation was wrong, I offered that we could instead install a 4x3 fernco insert donut and he agreed, that would be ok making the fitting a 4x3 san tee.. which is essentially the same... But here we are.

 

[Reach4]

Looking at UPC 310.5 from the original post, I am considering the word "enlargement". The exception for 4x3 closet bends is because that does appear to reduce with respect to flow, or to enlarge if you are picturing the pipes from a downstream to upstream direction. So I am making a plumbing code semantics observation.

Anyway, clearly the thing they are prohibiting (except for the exception) is pipes that are bigger on the upstream end and get smaller at the exit end.

 

[Terry]

Inspector called me back. I still believe that his interpretation is incorrect. He said that the san tee is 4" and that using a 4x3 reducing fitting is an obstruction.. saying we reduced the size. However, after not being able to convince him that his interpretation was wrong, I offered that we could instead install a 4x3 fernco insert donut and he agreed, that would be ok making the fitting a 4x3 san tee.. which is essentially the same... But here we are.

Wow!
Yes, the 3" trap arm was all it needed.
Would he have been okay with this one?

 

[Jeff H Young]

That's what I thought if it was a 3 inch santee no problem but a 4 inch santee no go . so basically he would call you on putting a bushing in a santee eg reducing for the vent to 2 inch. or had it been plastic 4 inch santee and you put a 4x3 bushing for a w/c.
Assuming he would call image in post 13 (I'm good with pic in post 13) I'm thinking the code is meant to refer to the opposite so that something doesn't go down the pipe and get stuck with no way possible to go down. the santee isn't obstructed because the 3 inch reduction was specifically allowed for closet bends then the 3 inch INCREASES to 4 inch (the opposite of an obstruction)
might be a technicality I that could be the proper interpretation but I don't think so if he is right then I think its more of a mistake in the code than anything legit.
So if I put a 4 inch wye underground on side and bush the wye to 3 inch on the sie or upper end I'm not obstructing
if I bushed down the downstream end that's obstructing flow . this is what that code means to me.
I didn't read completely tuttles discussion with inspector , oh hell no if its a 4 inch santee and he says a coupling and reducer is illegal than a reducing donut doesn't change anything he is making this stuff up now If one is illegal they both are he just is full of it.

 

[Tuttles Revenge]

The more I think about it the more frustrating it seems.. I tried to convince him that he was citing the wrong code but he kept going back to the oversized trap / scouring argument even after I pointed out that toilets have their own integral trap, which he agreed.

OH well.. Theres only so far I was willing to argue. The agreed fix is relatively easy. Way less work than the whole house backwater valve situation on that property.

He was appreciative that we even bothered to pull permits and get our work inspected. He said that approximately only 30% of plumbing work in Seattle gets inspected..

 

[Jeff H Young]

Im frustrated and its not even my job LOL. i dont read that code as having anything at all to do with your install. And again it is the opposite of an obstruction like running a 2 inch line into a 6 inch .
I dont know a polite way to challenge this call even if you fix to his liking perhaps a senior inspector its more than the work its knowing for next one and he couldnt even spout the code section it violated

 

[wwhitney]

I would say that in general the last sentence of 1003.3 does require that a fixture trap arm be a consistent size throughout, which matches the size of a field installed trap. E.g. If you on a shower you have 2" trap -- 2" trap arm -- increase size to 3" -- then shower dry vent, that increase in size from 2" to 3" seems to violate the last sentence of 1003.3, with a 2" trap connected to a (partially) 3" trap arm.

However, it makes no sense to apply that rule to a WC, since the the trap is internal to the WC and of unknown size, likely smaller than 3". So I don't see increasing the WC fixture drain size from 3" to 4" before the fixture is vented as violating 1003.3, when WC fixture drains never comply with 1003.3 anyway.

Cheers, Wayne

 

[Jeff H Young]

technically its not really a trap arm , from the standpoint of needing to be not siphonable you could use a wye or combi and why would a donut be exempt. yea he is bastardizing the code but there could be another portion or a linguist maybe able to disect the wording in his favor .

 

[wwhitney]

technically its not really a trap arm

Yeah, I checked on that angle (as then there would be no 1003.3 violation), but the UPC defines the trap arm as:

"Trap Arm. Those portions of a fixture drain between a trap and the vent."

So it is a trap arm. I just prefer to call it a fixture drain, since it has so many other exceptions to the trap arm rules.

Cheers, Wayne