I have a plumbing stack that is a 3" cast iron pipe inside a concrete block
wall. The concrete block wall was chiseled out to make room for the pipe
when the house was built.
I am moving a sink and hired a plumber to move the drain. The lav drain
ties into this stack. To move the lav drain means he has to cut the vent
pipe where the tie in will be. However, when I pulled back the sheet rock
and exposed the pipe, I found the entire cast iron pipe from top to bottom
was compeletly filled in with solid concrete. So 30 years ago they chiseled
out the block wall (this is an internal block wall separating the bathroom
from the garage) for the pipe about a 12" opening, then the pour solid
concrete over that opening.
The plumber told me I need to expose the cast iron pipe, a 4" clearance all
the way around the pipe from the slab to 2 feet high so he can work.
So now I am wondering what I need to do. I already tried a hammer and
chisel and after half an hour I did not make too much head way so I think I
need an electric tool to help.
I am concerned about using doing something that may damage the pipe. The
plumber told me if I use an electric chisel or jack hammer I may slip and
break the pipe, and if I did the cast iron will crack longitudinally and if
that happens I may have to replace the entire CI pipe so I need to be very
I thought about using a hammer drill with a largest possible masonry bit
(1") and drill holes every 2 inches all the way in and try to chisel chunks
of it out? The block wall is 4" thick so the concrete fill is 4" thick.
Will this work?
Or should I get an electric chisel?
Thanks in advance,