Attn. Plumbers Residential home question

/ Attn. Plumbers Residential home question #1  

Pixguy

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Ok, a gc is building a home for us and the waste pipe has been run in a full basement and there is an area where the master bath line is dropped at a 45° to drop below the main duct that runs along the support beams. The drop is approx. 30 and then takes a 90° turn.

My question is coming from a layman who always thought that the waste pipe should always drop 1/4 per ft and that a fast drop like that will allow the liquids to run past the solids and I will eventually have a buildup at that 90.
Behind that area is the toilet of course, dbl. sink, shower(used twice daily) and a tub(used approx. once a week)

I will provide a picture today if I get to the site. Am I worried needlessly? Will the additional liquids from the shower wash down anything left behind? I would ask the gc or plumber but they would likely just cya and tell me itç—´ fine and I want to take care of this before we close.
 
/ Attn. Plumbers Residential home question #2  
Two 45's to offset under duct and then a horizontal 90 degree turn? Fine if 90 is a long sweep fitting. Or is it a 90 from horizontal to vertical? Which would also be fine. Problem with liquid outrunning solids is generally when slope exceeds 1" or so per foot of run, but is less than a 45 downslope. Also usually occurs on long downslope runs--think running down a hill outside the house. You have no worries on this one.
 
/ Attn. Plumbers Residential home question #3  
+1 I've got a 45* drop for 3' to 4' in my main 4" sewer line then goes back to the normal slope. It's been 6 years now and no problems with it.
 
/ Attn. Plumbers Residential home question #4  
I doubt you will ever have an issue. With the constant use of water, it will push anything thru. Especially PVC. it doesn't rust or corrode list cast and cause friction. I have a toilet at my dad's house that they put the Y in backwards, and it flows in upstream. Been like that for 80 years now. No issues. Only found it when I had to break into a ceiling to fix some water lines. Just laughed and said WTF.

A lot of older houses (and new in some areas) have U-traps on the main line. That always seemed like a bad idea to me, but it works as long as you have constant water usage.
 
/ Attn. Plumbers Residential home question #5  
With PVC pipe, it's pretty much impossible to have any issues with solids building up in a pipe. All of those issues where back when cast iron was used, and everything got stuck in that pipe!!!
 
/ Attn. Plumbers Residential home question #6  
. . .My question is coming from a layman who always thought that the waste pipe should always drop 1/4 per ft and that a fast drop like that will allow the liquids to run past the solids and I will eventually have a buildup at that 90.
Behind that area is the toilet of course, dbl. sink, shower(used twice daily) and a tub(used approx. once a week)

In the world of drains anything between vertical and 45ー is considered vertical. As far as the 90 which I take to be at the junction of two 45ー (an hence vertical) runs, it should be less of a choke point than 90's going from vertical to horizontal, e.g. the closet bend under the toilet.
 
/ Attn. Plumbers Residential home question #7  
You interviewed and researched contractors before you hired them. Now is the time to trust the folks you hired. The plumbing is fine. Their is the ideal world and reality. Reality is HVAC and plumbing are always at odds. It sounds like your HVAC and Plumbing contractors did a fine job getting everything run......let go of their ears. I’m sure the job will go well. You will end up with a nice home. Enjoy this exciting time!!
 
/ Attn. Plumbers Residential home question #8  
Trying to understand the problem. My 2nd floor drains drop 8' to the basement ceiling, crosses the room, then drop another 10' to go under my footer. Not sure how a short drop to go under ductwork would hurt it.
 
/ Attn. Plumbers Residential home question
  • Thread Starter
#9  
I have no problem letting it go if you guys tell me it’s fine. I haven’t said anything to them.

Here’s the area I questioned.
FD126FBC-6AB8-411F-A7FD-4C2BD0B63A9B.jpeg
 
/ Attn. Plumbers Residential home question #10  
Where is the purple primer?
 
/ Attn. Plumbers Residential home question #11  
They could have used clear primer. The smearing of the writing would suggest they used something. I don’t see any evidence of glue either so I’m not sure that the whole thing isn’t a dry fit.
 
/ Attn. Plumbers Residential home question #12  
I wouldnt like it that low. I also would put a cleanout on the end of the lower run.
 
/ Attn. Plumbers Residential home question #13  
I wouldnt like it that low.
It has to be that low to clear the duct all the way to the right in the photo. Or, he'll need another step down.
 
/ Attn. Plumbers Residential home question #16  
Where is the purple primer?

Plumbers are a funny bunch about “marking” their work. One wants colored primer and glue so he knows where he’s been and others want no marks at all- they think it looks more professional! It all has to pass a pressure test which DWV should never see after that.
 
/ Attn. Plumbers Residential home question #17  
I think it no doubts looks better with the clear glue but than again it’s a sewer drain pipe and the colored would be easier to work with.
 
/ Attn. Plumbers Residential home question #18  
Inspectors here will give you a red sticker her if they don't see purple primer.:drink:
 
/ Attn. Plumbers Residential home question #19  
Plumbers are a funny bunch about “marking” their work. One wants colored primer and glue so he knows where he’s been and others want no marks at all- they think it looks more professional! It all has to pass a pressure test which DWV should never see after that.

Every leak that I've dealt with on PVC has been from somebody not using purple primer. In cities that have Inspectors that I've dealt with, when they see PVC, they want to see purple primer. While I understand that drain lines are not under pressure like PVC water lines, and you can get away using a glue instead of the two part system of softening the PVC with the purple primer and then welding the PVC joint together with the Clear Solvent, if there is going to be an issue in the future, it will be at the joint.

Has anybody ever seen a leak on PVC where purple primer and Heavy Duty Clear PVC Solvent was used?
 
/ Attn. Plumbers Residential home question #20  
Has anybody ever seen a leak on PVC where purple primer and Heavy Duty Clear PVC Solvent was used?
Yes, but they did not insert the pipe into the socket to the proper depth. When it rained and the trench filled with water the fitting came apart. It had not properly welded itself. I suspect they let the glue dry to long before inserting the pipe into the socket. But, otherwise, if the connection is done properly, it doesn't come apart.
 

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