Cast Iron trouble under slab

[Mybackhurts]

Hi-1950s house, unfinished basement and keeping it that way. (3) stacks each elbowed in back of house, go to lateral run under slab and out the front of the house to the street service. An elbow cracked and I jackhammered it out, replaced the stack with pvc and connected to CI in slab. Looking in slab pipe, the bottom of the pipe is paper thin for at least 10 feet.

Instead of replacing 3 lateral subslab lines, I’m thinking of cutting out the (3) stacks in the basement, running pvc along the interior wall up high (9’ basement ceilings) hung from joists, add a drop and street elbow at the front of the house. Any trouble with that?

 

[Sylvan]

Hi-1950s house, unfinished basement and keeping it that way. (3) stacks each elbowed in back of house, go to lateral run under slab and out the front of the house to the street service. An elbow cracked and I jackhammered it out, replaced the stack with pvc and connected to CI in slab. Looking in slab pipe, the bottom of the pipe is paper thin for at least 10 feet.

Instead of replacing 3 lateral subslab lines, I’m thinking of cutting out the (3) stacks in the basement, running pvc along the interior wall up high (9’ basement ceilings) hung from joists, add a drop and street elbow at the front of the house. Any trouble with that?

I see no problem as long as you have pitch and Clevis hangers for support and install clean outs

 

[Sponsor]

 

[Reach4]

Hi-1950s house, unfinished basement and keeping it that way. (3) stacks each elbowed in back of house, go to lateral run under slab and out the front of the house to the street service. An elbow cracked and I jackhammered it out, replaced the stack with pvc and connected to CI in slab. Looking in slab pipe, the bottom of the pipe is paper thin for at least 10 feet.

Instead of replacing 3 lateral subslab lines, I’m thinking of cutting out the (3) stacks in the basement, running pvc along the interior wall up high (9’ basement ceilings) hung from joists, add a drop and street elbow at the front of the house. Any trouble with that?

What you describe sounds similar to "overhead sewers". It is often done to prevent sewers from backing up into basements, and in some areas, there may be programs to assist with payments when done for that purpose. So that may not be a thing in your area, but you still might want to look at that. The project usually includes adding a pit/basin with an ejector pump that feeds sanitary sewage needs from the basement.

Try this Google search: "overhead sewers" virginia or just "overhead sewers" for construction descriptions.

Note that the usual 3 and 4 inch PVC for DWV is foamcore, but for people who like to go stronger, there is dual-rated pvc (DWV and pressure) and even triple-rated adding a well casing rating. Fittings are compatible. There is not a big difference in quieting, and I forget which PVC is quieter.

 

[John Gayewski]

This post is from 2024.