Kitchen sink waste pipe sizing and other related questions

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Travis K

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I tore out and replaced some bad pipe in the wall under a kitchen sink today. A little history on this Job. I am a GC and tile contractor, Hi Jim. I was doing a bathroom remodel for this customer last year and for some reason I ended up looking under her kitchen sink. I informed her that the whole bottom part of the cabinet was warped, rotten, and that she should not keep ignoring it because there is a more serious problem under there. Keep in mind that this customer is a tad ditsy when it comes to some things. I asked her if there were any leaks that she saw in the past and she said that she just wishes them away. She also says that she always starts sneezing when she sits at her kitchen nook and eats breakfast. I told her that it was probably a wall full of mold.


So now 18 months later she has me over there fixing all sorts of random stuff. I start tearing out the warped particle board bottom of the kitchen sink base. I notice that there is clearly an unpainted sheet rock patch in under this sink. I ask if she had ever had work under done under there, she says no. Keep in mind she is ditsy. The house has other plumbing issues that were fixed by the builder during construction, so I figured maybe it was done 30 years ago while the house was built. So I continue.

I remove the sheet rock and there is clearly some sort of current leak. I have her look under the sinks while I go outside and spray the window/exterior wall with water. Within a minute she sees water.

Issue number 1, the clean out for the sink is a wye, horizontal through the stucco and not sealed correctly. Rainwater can go right through the house and into the stud bays, etc. Good things its California and it hasn’t really rained in 3 years. The wye/cleanout is just to the right of the stud on the right. https://terrylove.com/forums/index.php?attachments/20210824_131514-jpg.76230/

My thought is to just get rid of the clean out. There is no easy and correct way to seal up a protrusion through a southwest wall with no eve/overhang of any type to protect it. Is this oaky? Not asking code or legal, just I assume everything is going to be fine without it. And aiming the cleanout so that its under the sink and inside the house isn't really an option. The waste pipe runs parallel to the base of the cabinet and will just hit the particle board shelf/base. I suppose that I could still put one in but I would rather have to cut the drain pipe to snake it in the extremely rare case that it clogs in the next 20 years.

2nd question. Is it okay to run 2 inch pipe, p trap, etc up to the tail piece of sink? The local store only had a 2x2x1-1/2 sanitary tee.


Oh and back to that previous repair. I was looking at the abs waste pipe in the wall and it looked somewhat new. It has current UPC code stickers on it. It looked just like the stuff I could buy from HD today and didn't appear 3o years old. I again ask the homeowner if she had ever had work done. I ask if her deceased husband would have done any work. She said no. Then 30 mins later she remembered that Boney plumbing did some work about 5 year ago. I asked her to find the work order if she could. https://terrylove.com/forums/index.php?attachments/20210825_162345-jpg.76231/

Reason being, As I cue the waste pipe back to where the clean out was I noticed a crap load of movement from the 90 that went from horizontal and down towards the foundation. I get in there with a light and the wrapping around the pipe in the concrete had been removed. There were 2 cracks pretty much all the way around the pipe in between the 90 and the coupler at slab level. Time for the roto hammer.

I dug down, cleaned up the pipe and rebuilt the waste pipes, minus the cleanout and with the additions of a 2" pipe that will run to the sink.
All fixed?https://terrylove.com/forums/index.php?attachments/20210826_164650-jpg.76232/
Unless I put a new clean out pointing inside the house. Can cleanouts be 1.5 inches? What if i put a long san tee 2x2x2 horizontal, aimed up at 45 degrees? I would put it between the stud and the 90 head up to the sink. I would cut out the section with the coupler. I am not opposed to a cleanout. I am just not that concerned so it needs to be minimal work.



So here is another question. That 2 inch p trap is going to take up more room under that sink. I suppose it doesn’t really matter. But that’s why I am asking here. Should I through a bushing or reducer in at the san tee and then build the p trap, etc out of 1-1/2 abs? Or use 2" pipe out of the san tee, then a bushing/reducer, to a 1-1/2 p trap, or 2" pipe, p trap all the way to the sink tail piece, then using a bushing and slip joint adapter. Does all of this make sense? When does a bushing get used instead of a reducer? I was taught that when following water flow, smaller to bigger gets a bushing whereas bigger to smaller ger a reducer.


And then finally. There was this hard, clear, crystal, crap on some of the pipes. I thought it might be flux or something that dripped off something else? I don’t think that I have ever seen it and thought that you all might know. https://terrylove.com/forums/index.php?attachments/20210826_171535-jpg.76233/

Oh and are there any good references or literature on plumbing code and doing it the right way? Those $20 books tend to be useless to me. I already know the basics. Like something that would tell me all of the laws that I am breaking by not installing a clean out in the kitchen. Or if a shower and toilet can share the same vent pipe if the drains are with in a foot of each other.


Well thanks for your time. I had to make another account because I wasn’t getting the password reset emails. And hopefully I can add some images of what I did to this kitchen plumbing.


Travis
 

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wwhitney

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Made it through your wall of text. More succinct questions will get you more responses.

1) I think a cleanout is required by the California Plumbing Code (CPC), and it's definitely a good idea. The CPC allows a 1-1/2" cleanout for a 2" pipe, so the question is whether a 1-1/2" trap adapter just upstream of your san-tee branch inlet is sufficient, or if you need to have a separate cleanout. I'm not clear on that.

2) You could use a 2" trap under the kitchen sink, and adapt to 1-1/2" tubular in the kitchen sink tail piece, but it would be unusual. Also, if it's a solvent weld trap, then I'd say you definitely need a separate cleanout. More typical would be to put a 1-1/2" reducer bushing in your san-tee and use a 1-1/2" trap adapter, with the rest of the trap arm in 1-1/2" tubular.

3) No idea what the substance is, but would be surprised if it was related to flux or soldering.

Cheers, Wayne
 

Jeff H Young

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You already piped the waste no big deal no cleanout. I would have but not that big a deal.
I see that calcium crystals on jobs . I should know more but think its related to solder, flux copper , dissimilar metals plus any condensation on outside of pipes. also the J hook seen strapping could contribute .
Again I'm not crazy about the lack of clean out nor alarmed by it. use a tubular trap it will access for cleaning. might try blasting water down full blast and check drainage before buttoning it all up
 

wwhitney

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If those are actually calcium crystals, the only source can be hard water. So if the water is coming from inside the pipes (versus outside the house), I would think that the joint has a slow, slow leak and the crystals have accumulated over a long, long time.

Cheers, Wayne
 

Reach4

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And then finally. There was this hard, clear, crystal, crap on some of the pipes. I thought it might be flux or something that dripped off something else? I don’t think that I have ever seen it and thought that you all might know. https://terrylove.com/forums/index.php?attachments/20210826_171535-jpg.76233/
  1. Is that photo upside down?
  2. Is the material pretty water-soluble?
California is more into cleanouts than most areas, it seems to me. One possibility in your temperate temperatures is to have the cleanout port outside. For a kitchen drain, the probable place to get a clog is where the flow turns from vertical to horizontal.
 

Travis K

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Made it through your wall of text.

Cheers, Wayne
Lol, yeah. Just wanted to make sure that you all knew everything.
I think I will run a bushing at the san tee and use a 2 piece, non glue type trap. Although I do hate those traps.
I am not too worried about the code on this one.
I assume is there cleaning out and inspection. There's nothing dangerous about not having a cleanout right. Besides the obvious of not easily being able to access it to clean it out.
 
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