Is this steep slope ok on the main drain line?

[CheesecakeLover]

Hello, in my dad's house which is new construction he showed me this section of the 4" main drain pipe. In most places it goes down at a slope of about 1/8" per foot. But then it goes down very steeply at approximately 45 degree angle to get down to the level of the city sewer outside. Is this normal?

EDIT: Not sure if you can tell, but it does straighten out at the very bottom with another 45 degree fitting just before passing through the CMU wall.

This image is a still screenshot taken from a video.

 

[Jadnashua]

As long as the pipe has at least the minimum, steeper isn't an issue. Keep in mind, it's often vertical in a taller building. Flat spots or reverse slopes are a problem. I think that they could have run that a little more efficiently, at least for space there in the basement.

 

[Sponsor]

 

[Reach4]

Seems not very respectful of basement floor space.

 

[CheesecakeLover]

Thanks. Perhaps I was overthinking this. You know how in a trap arm, you can't have the pipe too steep otherwise wet venting can't occur? I thought perhaps a similar rule might apply here but I guess not.

 

[Jeff H Young]

looks like a crawlspace more than a basement? whats it got 4 foot underneath. Unless there is a reason to run 1/8th I run 1/4 ipf grade.. Important to "respect the space" just as much as to respect the tradesman to make everything easy for him to make money on the job If I can save 10 mintes on a job do you think anyone could careless? So if Im inder a house trying to getrr done and its not a basement but a crawlspace Id dive down on 45s every time . Usually a general contractor or owner decides reasonably what spaces need to be saved and its communicated what the expexctations are .
To the op no not overthinking many peoples opinion is that execissive slope is bad. My arguement is that if over 1/4 inch perfoot is bad then why is there no maximum grade in our code book but a strict minimum standard.

 

[Breplum]

As per code: Plastic pipe is to be supported rigidly at 4' intervals.
That means either wood with a proper strap around it or the ready-made code approved ridgid hangers.
Galv. plumber's tape is not proper in any way. That allows the pipe to go off in too many directions.
FYI, plastic strap is not rated as adequate either. Plastic strap is only for tying off incidental branches and risers.
Galv. tape with plastic 10 mil tape over it screwed to a 2x works.

 

[Reach4]

As per code: Plastic pipe is to be supported rigidly at 4' intervals.

I think it may be more than 4 ft for 3-inch pipe, but your points still hold.