View Full Version : can I get a P-trap

11-15-2008, 11:55 PM
My older house has a S-trap on the kitchen sink-- a really messy one formed by multiple slip-joint fittings-- the bottom of the "S" is actually a 2" straight piece slip fitted in, not a one-piece S.. some of the slip fitting are leaking.. I want to make it right, but cannot get a P-trap in that leads to any drain or vertical vent in the wall (exterior wall).. when does a S-trap become a p-trap? If the vertical line coming up from the crawlspace was just extended to have an air gap and a new trap intersected it below the extension would that count or is a p-trap only a horizontal connection to a vertical pipe that drains down and vents up all the way to the roof or to a main vent stack? If so, I do not see how it can be remedied to meet code.
I also wonder many times why HD sells so many items not allowed by code in the jurisdiction they sell in- a big example is 14 gauge romex and push in connectors on receptacles which only take 14 gauge wire-- both are not legal, but 14 gauge is displayed right next to 12 gauge without comment..
I love it when their more skilled, usually senior citizen, employees who had to likely take the job to make ends meet, say something like " I would never use that product!" great confidence that builds.. but better than the usually younger workers, one of whom said he kind of knew plumbing (he was in the section giving advice) who was trying to show me ABS cement when I asked about pipe thread compound rated for natural gas...

11-16-2008, 12:55 AM
some explanation-
one photo undersink shows an angled, threaded copper pipe coming out of wall-- that did not drip much the first year and a half we lived here... now it does.. it fills up that tupperware about every three weeks.. I think it is an abandoned vent line that heavily condensates in the cold air in that outside wall.. could I just connect the new trap to that vent and solve both that drip and the venting?

You see the mess- is it slop photo worthy?

The big leaks are coming at the closer tupperware-- was a little after the disposal installer screwed with it while he added that flex line, tonight it was gushing at the slip joints in the two inch horizontal section -- might have gotten bumped- when I retightened them it seemed to work for now

in the basement photos you will see they barely slopped the horizontal.. one thought is to replace all of this horizontal basement stuff with ABS or PVC along with the under sink work, possibly putting the stub up under the sink in a better spot.. tie it into the copper vertical drain further down with a no-hub connector?

you can also see another mystery angled pipe in on of the basement photos that was also occasisionally dripping- I expect another abandoned line that had condensation in that cold wall.. in my early haste i filled it with spray foam and duct taped it-- which worked? I imagine it is filled with condensation water now, but the foam and duct tape had kept the basement from water

11-16-2008, 01:09 AM
another note on the slop-
in the vertical basement photo (image 0337) the copper drain line solder connection right to the left of the hanging strap also leaks slightly-- it appears somebody tried to add more solder, which is just flaking away.. one more reason get rid of this whole section with ABS or PVC? Preferences?

11-16-2008, 04:06 AM
Gawd I hate to say this but ....sanitary tee and an aav.

Lord forgive me.:rolleyes:

11-16-2008, 08:59 AM
I was going to say the same thing NH Master... Thanks for saying it first!

Also, in the basement that copper line looks back pitched. Get some hangers on it so that 1/4" per foot pitch to the drain is maintained.


11-16-2008, 09:29 AM
Pro supply houses also sell items that do not comply with code. Older houses are like older cars, they are out of date and some times need items that you would never use today. Maybe we should just junk all the old cars and tear down all the old houses and make everyone buy new every four years. You do need to be able to fix old out of date stuff without rewiring or replumbing the entire place.

I do like redwood's picture and it is a fix I have used for old houses when you want to upgrade. Some people just want a "cheap" fix without the more expensive upgrade.

11-16-2008, 09:49 AM
If you ever remodel the kitchen a through the roof vent would be a great idea.

I would also eliminate the flex line out of the disposer. The nooks and crannies in that flex line will trap food particles and give the disposer a case of halitosis.

11-16-2008, 10:38 AM
I wonder if the drain in the wall was vented properly. Why was it "capped" off, some illegal remodel?

BTW I wouldn't use the spring loaded terminals on the outlets anyway, use the screws.

11-16-2008, 10:48 AM
I didn't notice the capped off line before.
I wonder if it is vented through the roof and if it is what it would take to get it over to the sink.

11-18-2008, 11:47 PM
I have a feeling the two abandoned copper pipes (the one under the sink, angled up, and the one in the basement angled down are part of the original kitchen sink drainage, abandoned in some remodel--- the one dripping under the sink was maybe the vent and the other the original drain, but they are offset quite a few feet).. I "capped" the basement one because it was dripping what I think was condensate when ever the climate was right at the exterior wall... it is messy, but works-- if it is truly just a remnant not connected to anything else it seems to be okay.. the under sink one has been dripping a lot, but I also think it is condensation or rain water infiltrating that old vent.. I have heard from one plumber who saw it that in old houses in Alaska p traps into the exterior walls can be a real head ache, which is why they probably did the crappy remodel as an S trap-- it was almost certainly not down by a licensed plumber, based on the rest of the houses plumbing quality (i.e. every solder joint is a mess).
I appreciate the possible vent solution- it sounds like what I had in mind... the flex connector was installed buy the garbage disposal installer because a) he did not like the downward connection that comes with the disposals, and b) the previous disposal was jammed in there pretty badly-- it's rigid straight pipe was working away at all those slip joints with the vibration and actually had the right sink's tailpiece bent at an angle.. he suggested teh flex piece as a stop gap to avoid further damaging the existing slip joints-- which he did anyways.. I will try and eliminate it if I redo the whole she-bang.. what is the opinion on the need for a separate P-trap between thedisposal and the right hand sink's tail piece.. I have heard it actually causes more problems than it solves..

11-19-2008, 12:37 AM
sure enough- the added on horizontal section in the basemnet that you thought might be kinked- the solder had flaked away and it is loose- you move the vertical that goes into the cabinet up and down (you see it is only held by a thin wire) and the newer copper slides in and out of the older piece.. ughhh one more slight drip, but this is definitely dripping sink waste water into the basement... I see now a completely new PVC or ABS drain system from the sink & disposal down to that older copper, tied in with a no flex hub... wondering if instead of doing the air adapter should I just tie the new drain to that abandoned up-sloping copper pipe under the sink, assuming that is an abandoned vent that still reaches the outside air-- seems that may provide the needed venting and solve that pipes drip (since it would drip its condensation or rain water into the drain and not my tupperware)??

11-19-2008, 05:28 AM
The old line would have to be run over to the top of the tee where the p-trap conects to be an effective vent. It would also not be allowed to go below the level of that tee and would have to be pitched properly.

For the disposer use a sink tailpiece instead of the flex and the one p-trap you have will serve both.


To connect the pvc or, abs to the copper use a Fernco Proflex or, Mission Coupling designed to connect plastic to copper. One end will be thicker rubber with a smaller I.D. to compensate for the smaller O.D. of the thinner walled copper pipe.