replace BR sink cast iron plumbing with PVC?


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Old 07-16-06, 08:32 PM
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replace BR sink cast iron plumbing with PVC?

I'm doing a bathroom remodeling project and I want to replace the old under sink plumbing with PVC. Does anyone know how to attach PVC to the fixture drain line / drain stump?
 
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Old 07-17-06, 02:10 PM
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Do you mean that you wish to replace the chrome-plated P trap and connecting piping with a PVC trap and piping?

The connection to the in-the-wall drain is either cemented ABS (black plastic), cemented PVC (white plastic), soldered copper, cast iron or galvanized steel. The cast iron or steel would be likely if the house is more than 30 years old or your local plumbing code did not allow plastic when the house was built. In any event, the actual connection to the P trap piping will be by a threaded connection known as the "trap adapter" and this is (and has been for a very long time) standardized.
 
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Old 07-20-06, 06:44 PM
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f/u to replacing drain plumbing under sink

Thanks for answering. I pulled the escutcheon away from the drain stub and it appears to be cast iron. When I go to the Home Depot, do I just ask some guy for the adaptor?
Also, when I connect the PVC P trap to the tailpiece, do I just use connectors and hand tighten, or do I use that purple glue stuff? I've seen conflicting advice on different websites.
 
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Old 07-21-06, 03:27 PM
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If you have an escutchion that is sort of dome shaped then it is probably covering the trap adapter. It could be as simple as a threaded nipple into the fitting (most likely a tee) in the wall with a slip nut on the outer portion.

Most bathroom sinks use a 1-1/4 inch trap whereas other sinks will use a 1-1/2 inch trap. If the fitting in the wall is 1-1/2 inch then you will need a 1-1/2 nut with a 1-1/3 by 1-1/4 slip washer if your sink uses a 1-1/4 trap.

Most hardware stores and big box stores will have a pre-packaged trap kit that will have the trap, slip nuts and both sizes of slip washers. They are relatively inexpensive in PVC, only a few dollars as I recall.

DO NOT use any glue or cement on the trap parts. Do not use any teflon tape or thread sealant. The slip nuts with the proper washers are quite sufficient to prevent leaks. Hand tight is usually enough but if you are not very strong (or have arthritis like I do) you may use a wrench VERY gently to snug the nuts slightly.

Be sure to install the cone side of the slip washer AWAY from the nut and into the adjoining pipe.


Note: If your house and plumbing is really old you may have a much bigger job than I have described.
 
 

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