Believe it or not I have a 2-1/2 inch dia. cast iron pipe in my shower drain. Although a lot of people try and tell me that's not possible. Anyway, I'm doing a complete shower remodel and discovered that things have changed. I went in search of and actually found a 2-1/2 inch diameter flange for this shower, Amazing, I know. Think the guy who sold it to me said something about wiping the cobwebs off of it in a dark room. (Ha,ha) So, I know this is really interesting and all but I do have a point to this story. The old flange I pulled up looked like is was simply sitting on top of the pipe affixed with plumber's putty or some similar substance that has dried out, maybe caulk, cause they say the putty never dries out. My question is, the new flange has a rubber gasket/donut/"fernco type" shower drain connector that sits between the pipe and the flange, so by pressing this flange onto the pipe does that rubber gasket make a water tight seal? Also, the old flange just pulled right up. Did the original builders of the house make a mistake? Does this thing need to be applied with lead or oakum to the pipe? If so, that seems to defeat the purpose of the rubber gasket?
Cast iron shower drain
- Thread starter rgrinde
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Does the new flange/drain have a nut that compress the donut gasket or do you simply force the donut gasket into flange/drain. If you force the gasket, then i am wondering if you have a mop basin flange/drain. With the remodel why not change it all over to PVC/ABS, easier to do now than later.
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The flange/drain has a recessed area the gasket sits in and then fits/presses down over the pipe. I bought it from a plumbing supply and they said it was a shower drain. It seems snug but of course I guess I'll have to test for watertight. I was thinking of filling the bottom of the outside of the drain where it fits into the slab with silicone or wrapping plumber's putty onto the pipe where the base of the drain would connect when presses onto the pipe for for extra insurance. I suppose I could convert to pvc/abs but this method worked for the original builder and I have the part, amazingly. I was just hoping to see if anybody had any experience with this type of connection.
Perhaps a more direct question would be helpful to have answered: Has anybody ever used the Fernco donut gasket to connect a shower drain and what was your experience?
Perhaps a more direct question would be helpful to have answered: Has anybody ever used the Fernco donut gasket to connect a shower drain and what was your experience?
The first thing that needs to be done is to identify what you have for pipe. It's not 2-1/2". It may be 2" cast iron as the OD of 2" cast iron is close to 2-1/2". There is a strainer that is made for 2" cast iron. It's not uncommon. I'm hoping that's what you have. There should be four bolts that seal the strainer to your pan and there should also be a bushing that tightens down onto a rubber gasket that fit's between the pipe and the strainer. A picture of your strainer will help.
John
John
Here are some pics. You'll notice the gasket measures 2-3/8, and it fits over the pipe with an OD of 2-1/2 inches. I did remeasure and the pipe ID it is 2inches, so I hope I'm on the same page when talking about pipe sizes. Is it always ID you reference when talking about size? If you look at the bottom of the flange from the side then you'll see there's no bushing that would clamp down unless that's a separate part I'm unaware of but this thing is cast iron and would not compress anyway, and my guess is that this thing relies on the pressure of the pipe expanding/stretching the gasket to get a watertight seal. Everyone keeps saying switch to pvc but the original lasted over 30 years. Is there something wrong with this application?
That is the correct strainer. Just be sure the CI pipe is clean were the gasket fits over it. Put a little laundry soap on the inside and outside of the gasket. That will help to get it into place. You may have to tap it into place using a hammer and a dull cold chisel. Don't use anything that will cut the gasket. They can also be calked with oakum and poured lead but the gasket will do fine.
John
John
