Replacement sink

[oneirishpollack]

I am replacing a pedestal sink with a cabinet sink. The PVC drain pipe needs to be extended from the wall. Where would be the correct/best practice place to disconnect and add new pipe. It needs to come out approx. 4 inches to meet the new drain.

I included pictures.

 

[Jeff Handy]

Just saw off everything, starting at the elbow about an inch from the wall.
Cut nice and straight and accurate, so you are cutting the pipe just before it enters the start of the elbow.
That will leave you about a one inch long pvc stub coming out of the wall.
You might have to change that wall escutcheon for a new, thinner one, to make room for gluing on a new slip joint adapter.
By gluing, I mean you solvent weld it on using pvc primer and glue, you can get both for about $8.00 as a pair.
Very easy, watch a video on Youtube.
Then you can glue on a slip joint adapter, which is a compression type fitting.
Then you get a 1-1/2 inch P-trap kit, the wall tube from that kit will slip inside your new slip joint adapter.
Then you will probably need a short tailpiece extension kit, just a short pipe with another slip joint on it.
The tailpiece extension is used if the tailpiece from your new sink drain does not reach the slip joint fitting of your new P-trap kit.
You might need to get a plastic reducing washer, to adapt your 1-1/4 sink drain tailpiece to the 1-1/2 inch slip joint size of the new P-trap.
Or that washer might come with your parts you already have bought.
Home Depot or Lowes or Ace Hardware have all these common fittings.

1-1/2 in. PVC DWV Hub x SJ Trap Adapter

https://www.homedepot.com/p/100345781

 

[Jeff Handy]

 

[oneirishpollack]

Just saw off everything, starting at the elbow about an inch from the wall.
Cut nice and straight and accurate, so you are cutting the pipe just before it enters the start of the elbow.
That will leave you about a one inch long pvc stub coming out of the wall.
You might have to change that wall escutcheon for a new, thinner one, to make room for gluing on a new slip joint adapter.
By gluing, I mean you solvent weld it on using pvc primer and glue, you can get both for about $8.00 as a pair.
Very easy, watch a video on Youtube.
Then you can glue on a slip joint adapter, which is a compression type fitting.
Then you get a 1-1/2 inch P-trap kit, the wall tube from that kit will slip inside your new slip joint adapter.
Then you will probably need a short tailpiece extension kit, just a short pipe with another slip joint on it.
The tailpiece extension is used if the tailpiece from your new sink drain does not reach the slip joint fitting of your new P-trap kit.
You might need to get a plastic reducing washer, to adapt your 1-1/4 sink drain tailpiece to the 1-1/2 inch slip joint size of the new P-trap.
Or that washer might come with your parts you already have bought.
Home Depot or Lowes or Ace Hardware have all these common fittings.

1-1/2 in. PVC DWV Hub x SJ Trap Adapter

https://www.homedepot.com/p/100345781

So.....I started it before I got an answer......

I did cut it off close to the wall....but I welded a female coouple to it. The thought was if I ever had to go back, I could unscrew a sleeve versus any more cutting. Will a male/female tape connector be okay for a drain? Plumber putty?

 

[Jeff Handy]

You can screw a fitting like this into your female threaded fitting that you just welded on.

https://www.supply.com/browse?refinements=visualVariant.nonvisualVariant.Brand=PROFLO~BrandCategory=PROFLO+Copper+DWV+Fittings&nid=1885757&wmh_cid=6489572546&wmh_aid=80544121649&wmh_kid=815153906578&gclid=EAIaIQobChMIucSApdC15QIVSZyzCh3v8wgxEAQYAiABEgIh2fD_BwE


Not sure what or where you are asking about taped or plumbers putty for drain.

Be more specific.

Plumbers putty is often applied right at the hole in the center of the sink basin, to seal the top of the drain to the sink bowl.

Teflon tape is often used underneath where the drain tailpiece is sealed against the sink bowl from the bottom, although a rubber gasket is usually enough.
I use teflon tape because sometimes water will still sneak down the threads past the gasket.

You will need teflon tape or pipe dope on the male threads of the brass slip joint adapter I just showed you, where it threads into your new pvc female fitting.

 

[oneirishpollack]

By welded I meant, I glued a female connector on the stub-out. I was thinking I could then screw in a male sleeve and connect the trap to the joint. The female connector was to ensure any future changes would just involve unscrewing the connection vs. cutting the stub-out again....will this work?

 

[Jeff Handy]

Yes, everything is already explained, maybe you missed my reply above your latest reply?

 

[Jeff Handy]

PS just to keep out bugs or drafts, you can buy a hinged escutcheon, which will seal up that gap around the pipe, at the wall.
Every big box or hardware store will have them.

 

[oneirishpollack]

PS just to keep out bugs or drafts, you can buy a hinged escutcheon, which will seal up that gap around the pipe, at the wall.
Every big box or hardware store will have them.

Thank you for taking the time to share your feedback and expertise. I appreciate it.

 

[Rickyman]

View attachment 22288 You can screw a fitting like this into your female threaded fitting that you just welded on.

https://www.supply.com/browse?refinements=visualVariant.nonvisualVariant.Brand=PROFLO~BrandCategory=PROFLO+Copper+DWV+Fittings&nid=1885757&wmh_cid=6489572546&wmh_aid=80544121649&wmh_kid=815153906578&gclid=EAIaIQobChMIucSApdC15QIVSZyzCh3v8wgxEAQYAiABEgIh2fD_BwE


Not sure what or where you are asking about taped or plumbers putty for drain.

Be more specific.

Plumbers putty is often applied right at the hole in the center of the sink basin, to seal the top of the drain to the sink bowl.

Teflon tape is often used underneath where the drain tailpiece is sealed against the sink bowl from the bottom, although a rubber gasket is usually enough.
I use teflon tape because sometimes water will still sneak down the threads past the gasket.

You will need teflon tape or pipe dope on the male threads of the brass slip joint adapter I just showed you, where it threads into your new pvc female fitting.

Never screw brass into plastic, when hot water goes down the drain expansion of the metal will break the plastic.

 

[Jeff Handy]

I have that exact setup in my kitchen sink.
Which is the way it was built, or remodeled by previous owners.
A brass slip joint trap adapter receives the P trap which is pvc, and threads into the pvc piping going into the wall.

I pour gallons of boiling water down there when I make pasta, no problems so far.
I do usually run some cold water in the sink as I dump the boiling pasta water, but still way hotter than about 120 degrees which you would get from the hot water of a vanity faucet.

 

[Jeff Handy]

I did some quick research and did find references to brass male fittings causing leaks or cracks when screwed into pvc female fittings.

In most cases the brass fitting was over-tightened, then thermal expansion made it even tighter in the pvc threads.

Is there a pvc version of that brass trap adapter with the male threads?

I had just suggested what I have seen working for me, but I will always defer to pros or more experienced members on here.

 

[Rickyman]

I did some quick research and did find references to brass male fittings causing leaks or cracks when screwed into pvc female fittings.

In most cases the brass fitting was over-tightened, then thermal expansion made it even tighter in the pvc threads.

Is there a pvc version of that brass trap adapter with the male threads?

I had just suggested what I have seen working for me, but I will always defer to pros or more experienced members on here.

Since they already glued on a female adapter, I would glue a pvc male adapter into a pvc trap adapter back to back and screw it in to the female.