Currently renovating the bathroom on the upper floor and have reached the point where it's time to break up the old cast iron pipes (house built in '66). I'm a bit worried that I might risk going through the slab. I've measured and estimated a bit and concluded that the bottom of the 110mm pipe could be as far down as 40-50mm from the ceiling below. Is there a risk of going through?
Can the load-bearing capacity be compromised? It doesn't feel good to chisel a lot in the cast vault, but at the same time, the existing drainage wouldn't contribute to any load-bearing capacity...
Can the load-bearing capacity be compromised? It doesn't feel good to chisel a lot in the cast vault, but at the same time, the existing drainage wouldn't contribute to any load-bearing capacity...
Yep, there is a risk you might go through. But if you're extremely careful, you can get away with just a few cracks even if there's as little as 20 mm under the shoes on the drain. If you go through, it's quite easy to repair, as it will just be small pieces that detach.
As for the bearing capacity, you have to chisel quite a bit to jeopardize it. If you only chisel around the pipes and don't cut a lot of reinforcement, it makes very little difference to the bearing capacity.
As for the bearing capacity, you have to chisel quite a bit to jeopardize it. If you only chisel around the pipes and don't cut a lot of reinforcement, it makes very little difference to the bearing capacity.
When I snaked the drain and lifted out the floor drain, the underside of it was painted with white ceiling paint, and I ended up with a hole 100mm in diameter down to the basement... but the advantage is that you can easily see if the drain leaks. ;D
Go full throttle, because it definitely will!!
/Per
Go full throttle, because it definitely will!!
/Per
The thing about the drain clearing tonight was quite a truth with modification :-/
I have no sense of how far out from the pipe I need to chip away, so I hesitated for two hours and still haven't loosened anything. However, it is chipped to about half the pipe's depth, how much is actually needed? Can you pry it up with a crowbar if you just manage to loosen one end?
I realized at the same time that the 50mm pipe to the sink was a 90mm pipe that then bends up outside the bathroom to become a vent. Sigh, even more to chip away and fiddle with...
I have no sense of how far out from the pipe I need to chip away, so I hesitated for two hours and still haven't loosened anything. However, it is chipped to about half the pipe's depth, how much is actually needed? Can you pry it up with a crowbar if you just manage to loosen one end?
I realized at the same time that the 50mm pipe to the sink was a 90mm pipe that then bends up outside the bathroom to become a vent. Sigh, even more to chip away and fiddle with...
Well, half might be enough, but sometimes you might need to go 2/3 of the depth. But those cast iron pipes are really tight together, so you need to loosen them at both ends to pick up a piece. However, they are easy to break with a hammer/sledgehammer and chisel. Be careful with the connections where you will attach the new pipe; they must not crack when you're removing the old pipe from them.
Now I'm a bit off-topic =) So the joint between the old cast iron pipe and the new plastic pipes should happen in the existing cast iron socket? Is that the only option if you want to be able to seal it all over again (I've seen some kind of rubber socket with hose clamps too)?jon_h said:
Sigro, for example, has a shrink socket which I assume is used when entering the existing socket (shoe?) on the cast iron pipe, is that the right thing? What is their transition coupling Fernco used for in that case?
Now we are far outside my expertise, but it is indeed possible to connect in places other than in shoes. I just meant that if you want to connect in a shoe (for example, right at the branch of a vertical stem), you must not damage the shoe. You might want to throw the other questions into the plumbing section of the forum.