Long horizontal drain pipe run clogging regularly

[SWB]

Update

Thanks, guys, for all your help and advice! Here's an update.

My wife and I completed Phase 1 of this project on Saturday: buying all the fittings we might need and tearing out the old pipe. What a stinky, messy, disgusting mess that was! Good thing we have an unfinished basement!

Here's some sections of the second (14-foot) length of pipe after they were cut out:

Yuck!

The entire length of this section was pretty much the same; the first (16-foot) section was much cleaner. Both were pretty much what I expected, except I expected the gunk to be a soft sludge; instead, much of it was rock hard.

Has it been snaked?

Not professionally since we bought the house two years ago, but I did attack it with a hand snake last year. It helped, but when it clogged again this week, I resolved to actually fix the problem rather than just snaking it again.


After removing the pipe, I studied more closely the point where the pipe enters the basement from the sink:

My original plan was to cut this off right above the 90-degree bend and install a new 90-degree bend about an inch or so higher, thus increasing the slope towards the ductwork. That's still what I'd like to do, but notice how the pipe comes out right against the 2x10. The original installer had to burrow out part of the 2x10 to provide enough room for the flange of the elbow. If I remove this elbow, I'll be facing the same problem. How do I burrow out the 2x10 around the pipe without damaging the pipe in the process? Note that this pipe heads up into an exterior wall behind the kitchen cabinets, so there's no access from above.

Alternatively, I could leave the existing elbow alone and run new pipe from the exit of the elbow. This would give me only 0.2"/foot of slope, but it's seemed to work okay thus far: all of the blockage was in the second section that sloped at only 0.1"/foot. This section had a thin layer of soft sludge, but was generally clear.

Thoughts? Install a new elbow an inch or so higher (how to deal with the 2x10?) or leave it alone and live with only 0.2"/foot of slope for 16 feet?


Next topic: the new wye at the end of the run. I could go with a long bend:

Or I could go with a 45-degree wye:

I can mount the long bend higher on the 3" vertical, minimizing the intrusion into the living space. On the other hand, the 45-degree wye provides a steep slope at the end. I'd rather go with the long bend unless it could cause a problem.

(Ignore the location of the cap on the 2" pipe in these photos. It's not welded on yet; I just stuck it on dry to block any sewer fumes. I'm going to cut off that remaining length of pipe and cap right by the wye.)

1/4" per foot is not the minimum, it is the pitch you want. Too much pitch can be just as bad as not enough. ... In theory and engineering design 1/4" per foot is the correct pitch for water and solids to evenly flow downstream.

So it seems that too little slope is bad, then around 0.25"/foot is good, and more than that is bad ... except that at some point as the slope becomes more and more vertical (maybe around 45 degrees?), it obviously becomes good again. Interesting. I would like to learn more about this. (I can't help myself; I'm an engineer, and I always have to know how and why things work.) Can you direct me to a book or website that discusses this in more detail?

 

[hj]

pipe

Going back to the "too much pitch" statement. EXTENSIVE testing has proven that there is no truth to the "solids get left behind" theory. If that were the case pipes with the maximum pitch, namely vertical, and 45 degree slopes would be illegal.

 

[Sponsor]

 

[Toolaholic]

PIPE , question for you

Do You Have Some Documantion On This You Can Share ?

I,d Appreciate It Thanks

 

[Toolaholic]

swb

this is the best post .why not bring it to the attention of the building dept.

there is a name of the inspector that signed it off. i.ll bet a $100 he never worked in the trade,and was a political appt.

also the plumb. cont. should get these pix and pay you well for your time!

this work is outragous!

 

[Master Plumber Mark]

lowering the wye

what you posted will work real good....

you might even want take that 3 inch wye down as

low as possible.... a lot lower

what MR HI said is right,
you can give it all the fall you want
nothing is gonna get left behind......




make the 2 inch take a steep dive down to the 3 inch wye.


just take that 2 inch back as far as you can and

give it all a good amount of fall....


it will work fine

just ease up on the bacon grease

 

[Dunbar Plumbing]

Hydraulic Jump is common where the solids build up a few feet beyond the base of a vertical stack if a 90 is used at the base. Code requires a turn of direction of double 45's to control this problem. This usually is required on buildings more than 3 stories high/40 linear feet of vertical stack.

 

[Plumguy]

Going back to the "too much pitch" statement. EXTENSIVE testing has proven that there is no truth to the "solids get left behind" theory. If that were the case pipes with the maximum pitch, namely vertical, and 45 degree slopes would be illegal.

Comparing horizontal piping and vertical piping is like apples and oranges. However, I'd like to read that info, because personally I don't care for engineers and since they designed the plumbing system that we all know and love I'd like too prove them wrong!!

 

[SWB]

Hydraulic Jump is common where the solids build up a few feet beyond the base of a vertical stack if a 90 is used at the base

I did a Google search, and it looks like this occurs when a long vertical feeds into a horizontal. Is that right? Not sure how this is relevant in my situation ...

just ease up on the bacon grease

I suspect most of that was donated by the previous owners. The house is 14 years old, and we've only lived here the last two.

personally I don't care for engineers

Uh oh ... Did I mention I'm an engineer? I meant racketeer! Yeah, that's it, I'm a racketeer! ... (Wait, is that worse?)



Any insight into how to burrow out the 2x10 for a flange?

Dremel tool? Grinder? Recipricating saw? Avoid the problem and just live with 0.2"/foot slope for the first 16 feet?

Thanks!

 

[Dunbar Plumbing]

That was mentioned to the the plumbers on this thread, not you.

 

[Plumguy]

Hydraulic Jump is common where the solids build up a few feet beyond the base of a vertical stack if a 90 is used at the base. Code requires a turn of direction of double 45's to control this problem. This usually is required on buildings more than 3 stories high/40 linear feet of vertical stack.

Code is the same here. Horizontal to vertical you can use regular 90. Vertical to horizontal you must use long sweep. That's why I'd like too see more info about excessive pitch not being an issue as stated above.

If it is true that would mean that engineers have lied to us all these years!!? And just when you thought it could'nt get any worse...OH wait a minute lawyers wrote the codes!

 

[Plumguy]

Thanks, guys, for all your help and advice! Here's an update.

My wife and I completed Phase 1 of this project on Saturday: buying all the fittings we might need and tearing out the old pipe. What a stinky, messy, disgusting mess that was! Good thing we have an unfinished basement!

Here's some sections of the second (14-foot) length of pipe after they were cut out:

Yuck!

The entire length of this section was pretty much the same; the first (16-foot) section was much cleaner. Both were pretty much what I expected, except I expected the gunk to be a soft sludge; instead, much of it was rock hard.

Not professionally since we bought the house two years ago, but I did attack it with a hand snake last year. It helped, but when it clogged again this week, I resolved to actually fix the problem rather than just snaking it again.


After removing the pipe, I studied more closely the point where the pipe enters the basement from the sink:

My original plan was to cut this off right above the 90-degree bend and install a new 90-degree bend about an inch or so higher, thus increasing the slope towards the ductwork. That's still what I'd like to do, but notice how the pipe comes out right against the 2x10. The original installer had to burrow out part of the 2x10 to provide enough room for the flange of the elbow. If I remove this elbow, I'll be facing the same problem. How do I burrow out the 2x10 around the pipe without damaging the pipe in the process? Note that this pipe heads up into an exterior wall behind the kitchen cabinets, so there's no access from above.

Alternatively, I could leave the existing elbow alone and run new pipe from the exit of the elbow. This would give me only 0.2"/foot of slope, but it's seemed to work okay thus far: all of the blockage was in the second section that sloped at only 0.1"/foot. This section had a thin layer of soft sludge, but was generally clear.

Thoughts? Install a new elbow an inch or so higher (how to deal with the 2x10?) or leave it alone and live with only 0.2"/foot of slope for 16 feet?


Next topic: the new wye at the end of the run. I could go with a long bend:

Or I could go with a 45-degree wye:

I can mount the long bend higher on the 3" vertical, minimizing the intrusion into the living space. On the other hand, the 45-degree wye provides a steep slope at the end. I'd rather go with the long bend unless it could cause a problem.

(Ignore the location of the cap on the 2" pipe in these photos. It's not welded on yet; I just stuck it on dry to block any sewer fumes. I'm going to cut off that remaining length of pipe and cap right by the wye.)


So it seems that too little slope is bad, then around 0.25"/foot is good, and more than that is bad ... except that at some point as the slope becomes more and more vertical (maybe around 45 degrees?), it obviously becomes good again. Interesting. I would like to learn more about this. (I can't help myself; I'm an engineer, and I always have to know how and why things work.) Can you direct me to a book or website that discusses this in more detail?

Here is some reading for you, http://www.mass.gov/dpl/boards/pl/cmr.htm. You can email the board and their engineers with any questions! Please educate us when you get back. Thanks

Oh by the way, I think you should be ashamed of yourself for coming out here for free advice. You know you are going to google everything we tell you and question everything we have to say. I could tell you were an engineer(typical) from the beginning. Be honest you are going to do it you're way. Let someone who needs help benefit from this forum.

 

[SWB]

Oh by the way, I think you should be ashamed of yourself for coming out here for free advice. You know you are going to google everything we tell you and question everything we have to say. I could tell you were an engineer(typical) from the beginning. Be honest you are going to do it you're way. Let someone who needs help benefit from this forum.

Huh? I'm not sure what I wrote that touched a nerve, but it whatever it was must have lost its intended meaning or tone. If this in response for my seeking more detail about slope (too much, too little, etc.), I wasn't questioning the validity of your statement; I was honestly interested and curious to learn more. Some people like playing basketball; I like learning about stuff. Probably why I became an engineer. If this is about the engineer/racketeer comment, I was just trying to make a light-hearted joke. Sorry if it didn't come across that way. Whenever I try to try to write something funny in an email or on-line, it often backfires and doesn't come across the way I intended. I probably should stop trying.

I came to this forum as a homeowner seeking advice and wisdom from those more knowledgeable and experienced in plumbing than I am. I may be an engineer, but I'm the type that deals with electricity. I have very little plumbing experience (and until this weekend, absolutely none with running DWV pipe). Whenever I need to do something I don't know how to do or have never done before, I want to learn all I can before I dive in, lest I make some newbie mistake that I later regret. Yes, I've Googled a couple of things mentioned here when I didn't understand what the poster was talking about, but I'm not going around double-checking everything everybody says. On the contrary, I trust the knowledge and experience of the plumbers on this site far more than something "out there" on the Internet. Google searches tend to turn up a lot of conflicting information, some written by people who know what they're talking about, but a lot written by people who don't, and it's hard to tell which is which. I'd much rather come someplace like this, where all the experts hang out, for the real story.

Thanks to everyone for your help and advice. If I offended anyone else, I'm sorry; I didn't mean to.

 

[Plumguy]

Huh? I'm not sure what I wrote that touched a nerve, but it whatever it was must have lost its intended meaning or tone. If this in response for my seeking more detail about slope (too much, too little, etc.), I wasn't questioning the validity of your statement; I was honestly interested and curious to learn more. Some people like playing basketball; I like learning about stuff. Probably why I became an engineer. If this is about the engineer/racketeer comment, I was just trying to make a light-hearted joke. Sorry if it didn't come across that way. Whenever I try to try to write something funny in an email or on-line, it often backfires and doesn't come across the way I intended. I probably should stop trying.

I came to this forum as a homeowner seeking advice and wisdom from those more knowledgeable and experienced in plumbing than I am. I may be an engineer, but I'm the type that deals with electricity. I have very little plumbing experience (and until this weekend, absolutely none with running DWV pipe). Whenever I need to do something I don't know how to do or have never done before, I want to learn all I can before I dive in, lest I make some newbie mistake that I later regret. Yes, I've Googled a couple of things mentioned here when I didn't understand what the poster was talking about, but I'm not going around double-checking everything everybody says. On the contrary, I trust the knowledge and experience of the plumbers on this site far more than something "out there" on the Internet. Google searches tend to turn up a lot of conflicting information, some written by people who know what they're talking about, but a lot written by people who don't, and it's hard to tell which is which. I'd much rather come someplace like this, where all the experts hang out, for the real story.

Thanks to everyone for your help and advice. If I offended anyone else, I'm sorry; I didn't mean to.

I have also in the past been accused of emails,etc of being harsh or taken the wrong way. I'am also a newbie out here but certainly not in the trade.

Of course my posts are just my opinion and that is what is so valuable about this type of forum, getting different perspectives from pro's around the country!

I was serious about the website I provided you with, I would like feedback from you after you're research. Our code was just rewritten because most codes could be interpreted differently and would cause conflict between inspectors and plumbers! So, you get to look at the new version and click into sanitary drainage systems.

Oh by the way you did'nt hit a "nerve" and there was no need for an apology!! I would of never responded again to you're posts or had the decency to leave you that website if a "nerve" was struck. And you're thankfulness to those who contributed to helping you in you're project was very nice. See, my outlook of engineers is already starting to change! Thanks

 

[Plumber1]

plugged drain

That sort of layout just begs to be plugged. Has the drain ever been cleaned out before? As long as there is pitch it's ok.
I would put an 11/2' plug somewhere under the sink upstream of the last trap
and use it for a clean out. Rent or borrow a RIDIGED small drain cleaner and clean the drain the proper way. You might to put a small kink in the lead section of snake to make it flop around. Once you get the snake all the way into the 3''or 4" pipe, start to run water and back out the snake. The drain will be cleaned well and the snake will come back clean and not make much of a mess in the kitchen.

Oops, I got in too late!!!