I've got a plumber (who I really trust) coming out tomorrow to
temporarily cut into one of my main cast iron waste stacks. Reason:
there is a crack in the foundation right behind the stack that is
going to be treated tomorrow with epoxy injection -- and the stack is
in the way.
Once the crack in the foundation has been treated, the plumber is
going to replace the cut-out section of cast iron pipe with PVC.
My worries: the waste stack runs all the way up to the 2nd floor (and
out the roof through the attic, so technically through to the 3rd
floor). Everything I read says you MUST support the stack when making
a cut like this.
I asked my plumber (very reputable company and he has done alot of
work in this house for me -- all of which has been good) if he would
need to support the pipe before making the cut. He said "no" -- but if
when he began to cut he though it needed it, he would support it from
below (in the basement, where he'll be cutting).
I am worried about this. It's a beautiful 1930s Tudor-revival era
brick & mortar home -- built like a tank -- and I don't want to have
all kinds of damage to the plumbing connections in the walls that
connect to this waste stack when it gets cut (I hesitated even doing
this, but the crack in the foundation is something that appears to
have needed attention for a long time -- it gets water, although I've
fixed most of that problem from the outside).
Help. What do I tell my plumber? Do I insist that he install a brace?
Does it need to be a permanent brace? I can't imagine how tying in PVC
w/neoprene gaskets is going to support the weight of this stack. How
does this work? Should I be worried -- or trust this guy (who has 40
years of experience in this area, working on these types of homes)?
Thanks for any guidance you can provide!
It would be fairly cheap and easy to brace the existing stack
before cutting. It is a whole bunch easier to help keep it from
falling than to try to raise it back if it moves. PVC replacement
is probably fine, but it is no big stunt to replace it with cast
iron and no-hub clamps, or reinstall the piece that comes out if
he is using a chain cutter.
Keep the whole world singing . . . .
If the plumber is lucky, and the existing pipe doesn't crack, he may
be able to reuse the piece. It is never a good idea to count on being
lucky and the pipe being in good condition.
You can still get cast iron, and it is still used, but the bell-shaped
hub connections packed with oakum and lead are pretty much relics of
the past. Google Fernco to see what is generally used nowadays.
If not supported, the burden of holding the waste stack from dropping
would be the connections of the drain pipes from sinks, tubs, and
toilets to the waste stack. Unless there is some strapping somewhere
holding the waste stack, I would be concerned too.
Hi everyone -- thanks for the replies.
Well, the deed is done. The plumber came over early, I asked him to
please brace the pipe and he didn't object. He used steel strapping
and a masonry anchor -- but still insisted it wasn't going to move. He
decided to cut with a grinder/saw first, then finish with a Sawzall.
The cuts were made -- and the pipe never moved even a hair. Stood
firm. PVC with a new, lower, clean-out was soon in place with neoprene
So, I guess this pipe was indeed supported at each level -- but those
supports were not visible from the basement (finished ceiling).
Plumber also said that since the sink, tub, and toilet of the 2nd
floor bath tie into this stack -- all of those wyes are supported by
the floor joists as well.
Everything seems fine so far. This was complete at 11:30am this
morning (its now nearly 9pm EST) -- so I'm assuming I don't have to
worry about the pipe crashing through all levels and taking everything
These homes were built by German Catholics just before WWII -- they
are built like tanks, and I guess the plumber just knew that the pipe
was properly supported at each level.
Still a scary thought, though. But the cracks have been treated
(reason for cutting the pipe in the first place), and the replacement
PVC seems to be working fine.
Can I stop worrying now?
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.