Single to double vanity drain conversion

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chuckd83

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Hi all,

I am about to remodel my master bath (1955) and it has a single vanity. I'm putting in a double vanity and need advice on how to plumb the drain. I opened up the wall underneath the current vanity and took some pictures. Any help would be appreciated.
 

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Terry

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washer-galv-abs-2.jpg


The pipe gets cut out, and then wrestled out of the lead packing. The packing I pry out.

washer-galv-abs-3.jpg


I did this one for a washer, but going to the cast iron hub is the same. You can pick up a 2" hub x 2" pipe Fernco insert and run 2" pipe out the top.
I have not worked with lead piping, except to remove it.

New rubber bush, and a Mission coupling where the two sections of 1.5" meet on the vent.
Now it's a 2" p-trap and standpipe.

fernco_hub_4.jpg


A 4" Fernco, but they also make it in 2"

double_lav_sno.jpg
 
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chuckd83

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Thanks for the reply. Is it hard to get the lead out of the cast iron? It seems easier to cut the lead pipe 1-2" above and couple it to PVC.

New rubber bush, and a Mission coupling where the two sections of 1.5" meet on the vent.

Not sure I follow the need for a rubber bush to meet the vent. Can I not cut at the galvanized pipe and couple it to PVC using the mission coupling only?

Now it's a 2" p-trap and standpipe.

Can you explain this? Aren't bathroom sink drains 1 1/4" or 1 1/2" p-traps?
 

Erico

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Thanks for the reply. Is it hard to get the lead out of the cast iron? It seems easier to cut the lead pipe 1-2" above and couple it to PVC.



Not sure I follow the need for a rubber bush to meet the vent. Can I not cut at the galvanized pipe and couple it to PVC using the mission coupling only?



Can you explain this? Aren't bathroom sink drains 1 1/4" or 1 1/2" p-traps?

I just removed some lead from a hub. Once the pipe is out, the lead comes out fairly easy. It's soft and malleable. It will peel out like old caulk. Maybe with a little help from a screw driver.

I would cut all the lead out. Because it is soft and malleable.

The sink trap will be 1 1/4. You reduce after the elbo in the wall or with the elbo in the wall. I would reduce at the elbo with a 2 X 1 1/2 elbo. Come out of the wall with a stub of 1 1/2 PVC. Glue on trap adapter after the vanity is set. Use a nice chrome escutcheon to hide your cut. The glue on trap adapter will be the final reduction to 1 1/4.

I'm not a pro.

I think Terry is saying bushing at the bottom/floor and coupling up to where it meets the galvanized. You may need yo go to a plumbing supply place for bushing. I just did one for 4" and couldn't find it at the big box stores.
 
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chuckd83

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Got it, makes sense now. How do I get the pipe out? Cut it a few inches above cast iron and pull? I'm reading elsewhere that I need to heat it up so the lead melts. Not sure I want that dripping down the pipe as it's vertical, though.
 

Erico

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Got it, makes sense now. How do I get the pipe out? Cut it a few inches above cast iron and pull? I'm reading elsewhere that I need to heat it up so the lead melts. Not sure I want that dripping down the pipe as it's vertical, though.

Cut it up high enough so you have leverage and "wrestle" it out like Terry said. You won't need to heat it. At worst you probably would need a screw driver or sharp chisel to get behind it and pry to get it started.

I just did one last week. I was working in a bit of a hole and had to bust the 4" inch cast. Once I got started I hooked it with a little pry bar and pulled it out in two pieces.
 

Erico

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Thanks. Should I be concerned that I may damage the cast iron?

I don't think so. The hubs are pretty thick. I suppose you could soften it with a torch if you are worried about it but I don't think it's necessary
 
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Terry

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Plumbing code for two lavs is 2" pipe.
You can run 1-1/4" for one lav, and 2" for two. They don't make 1-1/4" DWV fittings, so plumbers install 1-1/2" and 2".

I would not put a torch on lead to remove it. With 2" hub fittings I can tork the pipe which loosens can comes out of the lead. I can then pry or drill out the left over lead.
For a double lav, I use a 1.5 x 1.5 x 1.5 x 2.0 fixture fitting.
 
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