Supporting vertical 4" cast iron soil stack

[branimal]

I'm renovating an 3-family home from the top to the bottom. As part of the renovation I'm replacing the plumbing and the 4" Hub soil stack with 4" Cast iron no hub.


I've replaced the soil pipe from the 3rd floor to the 2nd floor with CI NH.
I've replaced the pipe on the top floor leading to the roof vent with PVC.

My next move is to replace the portion of pipe from the 2nd floor to the 1st floor.

How do ensure all the piping above the 2nd floor doesn't slip down when I remove the portion of pipe from the 2nd to 1st?

Will a 4" riser clamp suffice to hold things in place? Are there better support systems to use?

Thanks!

 

[Geofd]

use a friction clamp resting on the wood in pic 3 at the bottom of pic 1 there is wood you could rest a friction clamp its hard to see all of pic 2 but maybe screw a piece of wood to the aluminum stud and use a friction clamp there