Question on Sewer Connection Plumbing

[Tidybuoy]

I starting a new half-bath build that is replacing a bathroom that was directly behind the new location. Part of the process involved removing some of the old cast iron 4" sewer pipe and I will be connecting plastic pipe to the main cast iron sewer line using a rubber connection piece.

My Question:
What is the difference between Black ABS and White PVC? All of the YouTube videos show plumbers using white PVC but I have also seen Black ABS used in the past. I'm just wondering what the difference is.

As a side note: Below are pics of cast iron piece that was concealed inside my wall of my 75 year old house. It took many hours to remove but I got er done.

Lower Right Shows Orig Cast Iron Embedded in Wall:



Exposed Cast Iron Was Being Used for Old Toilet Vent Line (there was a vent pipe extending to roof):


Drilling out Oakum & Lead Weld:


Part #1 Removed:


Part #2 To be Removed:

[Zeke]

ABS and PVC are very similar in sizes but you can't intermix the fittings. And each uses a different glue.

For some reason out west we use ABS almost exclusively It can be code in some places just like cast iron in commercial. I never saw PVC drain, waste and vent in PVC until I went east and then the Internet.

[908/930]

Not a plumbing pro, but have done lots. Up here we use ABS for drain, at least Ontario and BC. ABS is slightly more rubbery, less likely to crack if abusing it, does not require primer when bonding together. It is more likely to droop if you are doing long horizontal runs so requires a little more support.

[Icemaster]

Originally Posted by Zeke

ABS and PVC are very similar in sizes but you can't intermix the fittings. And each uses a different glue.

For some reason out west we use ABS almost exclusively It can be code in some places just like cast iron in commercial. I never saw PVC drain, waste and vent in PVC until I went east and then the Internet.

Ditto - never saw ABS as DWV until I came west. It was all PVC. IIRC the biggest difference in installation is one step vs 2 step. PVC you need a cleaner/primer on the fittings before gluing up, ABS needs only the glue.

[Zeke]

ABS is said to be stronger while PVC is more flexible. I guess that's why mobile homes are PVC.

[stevej37]

A few years back, I needed to attach 2.5" schedule 40 drain to cast iron. I did it with this...no leaks.
Not sure if that's what you mean.

[Tidybuoy]

Originally Posted by stevej37

A few years back, I needed to attach 2.5" schedule 40 drain to cast iron. I did it with this...no leaks.
Not sure if that's what you mean.

Similar. I will be using the items below. I'll be connecting directly to the end of the 4" sewer line after all the current drainage is removed. Basically starting from scratch and the whole room will be in the ABS Pipe and then connected below the house. The difference of mine vs. yours is that I will be connectiong 4" to 4" with the reductions occuring down stream in ABS.

[Tidybuoy]

I just asked the same question to one of our engineers at work. He told me that Black ABS is used if the pipe is being buried (mine's not). White can be used if the pipe is not in the ground. This is because the acidity of the soil destroys the white PVC. This is good to know because I found all the fittings I need in Black but was not able to find everything in white pvs.

[A930Rocket]

Having built homes in the south east for the last 35 years, all I’ve ever seen is white PVC. In the 90s, we did use cast-iron pipe in the walls to reduce noise but no longer.

[TimT]

This is because the acidity of the soil destroys the white PVC

What?

PVC pipe is allowed in most codes for direct burial...Usually after a certain depth, different schedule PVC is used, Sch 40 near the surface (frost line to 6') then Sch 80..I've never seen Sch 120..


And Fernco makes multitudes of adapter fittings.. just pipe such that you never present a leading edge to flow..

[Zeke]

Originally Posted by A930Rocket

Having built homes in the south east for the last 35 years, all I’ve ever seen is white PVC. In the 90s, we did use cast-iron pipe in the walls to reduce noise but no longer.

Probably the thicker walls and additional insulation made CI unnecessary?

[Tidybuoy]

I hate Oakum & Lead plumbing fittings.

I finally got the old sewer line removed - it took all day and I can barely move today.

What I'm Removing:


Removed: went thru a handfull of drill bits


Connecting ABS to Cast Iron: It took me 90 minutes to get that ABS into the Fernco gasket (very tight).


Tonight's Project: