Re plumbing drain line for new sink

[Mihomeowner]

I replaced a on the counter bowl type sink with an under mounted sink. So the drain is too high to accommodate the new setup.

See attached pictures... It looks like I need to lower the whole drain about 2.5"-3" to make it work (is that right?). I would imagine cutting the left side where the drain comes out of the wall and just creating a whole new drain. I can visualize it in my head but I don't know the fittings to use.

Please see pictures. This forum has always been very helpful to me throughout the years. Thanks in advance to everyone that helps here.

 

[FullySprinklered]

You don't have a problem. Your setup is illegal as it is. Dropping everything down could eliminate the s-trap that you have now and make for a better installation.

 

[Sponsor]

 

[Mihomeowner]

Thanks... can you point me in the right direction for what I need as far as fittings? Bring it right out of the wall directly in to a trap?

 

[Terry]

To drop it down, you may need an extension.
The trap arm comes out from the wall with a 2% slope and into a p-trap. Otherwise, the venting is lost and the trap can siphon dry and allow sewer gas into the home.

\

 

[Mihomeowner]

Thanks for the replies. So I can use this to extend the arm of the p-trap:
https://www.lowes.com/pd/Keeney-1-1-4-in-Plastic-Straight-Coupling/1071635
Is that correct?

Then I need one of these to cement in to the pipe coming out of the wall (after I cut off the existing stuff)?
https://www.lowes.com/pd/Charlotte-Pipe-1-1-2-in-x-1-1-4-in-dia-PVC-Trap-Adapter-Fitting/3132643

What will dictate if I need a 45degree elbow coming out of the wall? If there is not enough "swivel" in the p-trap to reach the drain?

If I need an elbow what should I be looking for on that? Would this be it?
https://www.lowes.com/pd/Charlotte-Pipe-1-1-2-in-dia-45-Degree-PVC-Elbow-Fitting/3572618

Then use some 1.5" PVC to come out of that (a short piece I guess?) then put the p-trap adapter on that? With the elbow right there, it won't allow the p-trap arm to get too deep in there. Is there a code for the minimum amount of p-trap pipe that should be inserted?

Also, you said it should have a 2% slope. Do you just eye ball this usually? How do you get that slope, from tightening the drain pipe portion of the p-trap?

Thanks again for help.

 

[Terry]

I stick with 1.5" for my fittings. There are far more fittings for 1.5" than for 1.25".
The top where it meets your 1.25" will have a reducing slip joint washer, 1.5" x 1.25"
You may need a coupling at the wall, and perhaps a 45. Depending on the layout, I either use a hub x hub 45 or a hub s street 45.
The p-trap you have now is 1.5"

 

[Mihomeowner]

Thanks again for your help.

So use something like this:
http://www.homedepot.com/p/1-1-2-in...igot-x-Hub-Street-Elbow-C48062HD112/100677990

Out of the wall then put a non-reducing 1.5" p-trap adapter on that like this:
https://www.lowes.com/pd/Charlotte-Pipe-1-1-2-in-dia-PVC-Trap-Adapter-Fitting/3132641

So far so good? Then use all 1.5" until you hookup in the black drain?

This is a 1.5" p-trap
https://www.lowes.com/pd/Keeney-1-1-2-in-Plastic-P-Trap/1070139

It looks like it says it comes with a "With 1 1/2-in to 1 1/4-in Reducer Washer"... so that should work for me right?

Can I insert the p-trap arm that close to the elbow? Is there a minimum amount that has to go in?

 

[Terry]

Pretty much like that. I would pick up a coupling, a 45, a street 45 and the p-trap.
You won't use all of that, but you only want one trip to the store.

 

[Mihomeowner]

What about the slope... is the wall stub sloped? So when I connect everything, there should be some slope already there?

When you say "hub s street 45", is this what you mean?
http://www.homedepot.com/p/1-1-2-in...igot-x-Hub-Street-Elbow-C48062HD112/100677990

Can I connect the p-trap adapter directly to that?

Also for the extra length, I am better off using a 45 degree hub x hub then adding some 1.5" PVC to bring the pipe close? Or should I use an 1.5" extension like this:
https://www.lowes.com/pd/Keeney-1-1-2-in-Plastic-Straight-Coupling/1071501

It seemed like it would make more sense to use the setup I described above... isn't PVC cement better (more water tight) than using a Slip Joint Connection?

Thanks again Terry

 

[Mihomeowner]

Well I got the one done. Of course I forgot to snap pictures but I will when I get a chance. But it worked out pretty good, put a new elbow out of the wall. I bought a 60 degree and a 45 degree. Of course I needed a 22.5 degree so back to the store I went. Now for the other side (this is two sink bathroom).

This other side might be a little tougher. There is no room at the wall to cut the elbow coming out. Also, where you see the black drain tube in the pictures, it's not all the way down. It's hitting the trap. Height wise, this setup looks good. Might not even need an extension going out of the top because there is still a good inch or two it needs to come down. But how can I rotate the whole trap assembly to get it out of the way of the drain?

Where the pipe comes out horizontally, put an elbow in there then run some 1.5" then put another elbow in to "swing it back" toward the drain pipe? I'm talking about doing a 90 degree elbow then a 180 degree which I am guessing would be two 90's. It would be pretty convoluted.

See pics... care to take a stab at this one?! Some of the pictures I took before putting the counter top back on.

Thanks again.

 

[hj]

From your description I think you created a completely "illegal monster".

 

[jamesdrainage]

A another idea By:- jamesdrainage

 

[Mihomeowner]

Interesting... what am I looking at?!

 

[Reach4]

Interesting... what am I looking at?!

I think he is trying to compete in the "illegal monster" drain picture contest. He is right-- his is much worse than the mihomeowner drain.

 

[MP_MKZ]

This is mine! On a serious note. I would cut the pipe near the drain. Cement an extension pipe followed by a 1 1/2 threaded Yie and then hook up the double sink to that. Am I even understanding what's going on here?