Master Bath Reno: Cast Iron Plumbing to PVC

If you have a fairly new house, your waste pipes are going to be PVC. I however, have an old house, so all of my pipes are cast iron. These pose problems over time because they rust and when they rust, like on the inside, the pipe dimension gets smaller and smaller. So basically overtime these pipes are either going to clog or disintegrate. Well, that’s a future me problem because current me has a different problem with these pipes.

So I first encountered a problem when changing out the drain to the shower. the shower pan is now sitting lower and so all this extra pipe is not needed as you can see in the photo above. I did not know that this was going to be a problem before putting in the subfloor. As you may recall from my Demolition post, there was water damage and I had to replace part of the subfloor. That would have been the PERFECT opportunity to fix this pipe, however I had yet to realize the pipe would need fixing.

Luckily for me, there was some access from the utility room. And by some I mean, there was a tiny space where I could access the pipe underneath. So this area shown in the picture above, I could barely reach with my full arm extended, plus the reciprocating saw. I stood on a ladder, propped my arm with my other arm and held on to the saw for dear life and hoped I was cutting at the correct spot and angle. the way I had to position myself, I could not look at the pipe and cut at the same time.

Believe it or not, I did it! And then I went back to measure it against the shower drain and…..it was still too long. That’s right, I had to do this process twice! Ugh! Well I managed to do it all again and success, we have a good fit for the pipe.

The next issue to address was attaching the PVC to the cast iron. Schluter (which was the shower system I was using) does not have any educational videos on their products to cast iron piping so I needed to do a little more research. Turns out there’s not really a standard method but you can find several different types of rubber sleeves to connect the two.

As you can see that what I ended up using and it hasn’t failed me yet! It was very easy to install, just use some muscles to shimmy that sucker on and a screwdriver to tighten the metal rings.


Rachel Williams

Artist | Designer | Educator

Making mistakes and fixing them, so you don’t have to