[Deck]

I have some extra heavy cast iron pipe in my basement and I will be replacing a damaged run of the pipe with PVC. Hundreds of pounds of the cast iron pipe (including the section I'm replacing) was supported by a single strap, probably 20 gauge. I added another strap (28 gauge from home depot) a while ago. I plan to order more of the heavy duty 20 gauge galvanized strapping.

Here is a picture of the pipe run with red underlining the sections of pipe that will be replaced by PVC.

How would you support the area of cast iron pipe that will remain and how would you support the PVC? I live in NY and I have reviewed the piping support section of NYS plumbing code. It seems it doesn't say specifically what supports are required, just the spacing. Does anyone know if seismic support is required in Westchester County? Also, sway bracing I assume will be required for the PVC since it will do a 90 degree turn horizontally. How would you guys sway brace this? Should I use some bracing on the cast iron house trap? It looks super heavy.

 

[FullSwing]

When replacing your cast iron pipe you should be using ABS not PVC. Just install a strap on the existing cast-iron where you make your cut to convert to ABS also install a strap in the middle of your ABS run so you should have added 3 straps total. Good luck!

 

[plumberinlaw]

I never used ABS, always used sch. 30, or sch. 40 foam core PVC. For that length of piping I would support both ends of the ci pipe and use shielded band clamps to connect the pipe. probably would not use a hanger for the PVC unless I didn't like the way it was hanging when finished

 

[Deck]

When replacing your cast iron pipe you should be using ABS not PVC.

Thanks but where I am in NY I cannot use that. I can use PVC but only in certain places.

For that length of piping I would support both ends of the ci pipe and use shielded band clamps to connect the pipe. probably would not use a hanger for the PVC unless I didn't like the way it was hanging when finished

Thanks. I have some Fernco proflex couplings to make the transition. How would you support the cast iron piping? I'd use regular band iron but that's what's on there now and it's all rusty. Is galvanized strapping ok or do I have to worry about galvanic corrosion? I don't want galvanic action or whatever it is to be caused by the zinc on the strapping, if that's possible.

Also I've been looking into these hangers called clevis hangers, are they worth the money?

 

[TheEplumber]

Use the type of plastic that your local code allows- I see PVC and ABS here.
Put regular gauge plumbers straping upstream of the house trap. Or you could use the clevis hanger- they are common on CI in commercial applications. For seismic, you probably don't need it- again, that's the commercial world.

Support your plastic at each end and at turns. Never exceed 48" span for the plastic pipe hangers/straps.
No need to be concerned about galvanic corrosion....