Kitchen Sink Plumbing Help

Users who are viewing this thread

Massdiyer

New Member
Messages
4
Reaction score
0
Points
1
Location
Mass
Hello,

Recently purchased a house and in the process of redoing the kitchen. The existing kitchen sink had the waste arm running at an angle through the adjacent cabinet, connecting to the main drain with a santee. We would like to move this waste arm so that it is not in the way, as a dishwasher will be going back in and the pipe would obstruct it. What would be the proper way to make the connection from the P trap to the waste pipe? We are planning on installing a garbage disposal, so at the current height I believe the existing santee is too high. Currently, the sink, bathrooms, and washer/dryer all have their own vent lines, so this is a direct vent for just the sink/dishwasher, with all other waste downstream of this. The beam stack to the right of the drain line has a structural 3x3, so I believe it would be too narrow to drill through.

The new sink cabinet will start to the right of the wood beam stack, centered under the window, so the drainage connection would need to make it to there. The hot/cold water lines will be relocated to the right slightly.

I've attached some pictures of the before/after (the drain pipe is plugged for fumes now). Sorry for the markups, I'm unable to get rid of them, but the old sink had the waste arm slope down after the p trap, and then through the cabinet and into the wall.

This is in NH (moved from mass recently).

Thanks for any help,

Sink 1.jpg
Sink 2.jpg
Sink 3.jpg
 
Last edited:

Terry

The Plumbing Wizard
Staff member
Messages
29,190
Reaction score
2,977
Points
113
Location
Bothell, Washington
Website
terrylove.com
I don't know if you should drill the support beam. Can you lower the santee in the wall and run the new trap arm in front of the post?
Some dishwashers allow some room behind, do you have what you're installing on hand so that you could measure that?
I've been running my trap arms at 16" above the kitchen floor because of the new 10" deep sinks.

Going from copper to plastic, you will need shielded couplings that have sizing on the rubber sleeves for the two sizes.
Copper x PL
 

Massdiyer

New Member
Messages
4
Reaction score
0
Points
1
Location
Mass
I don't know if you should drill the support beam. Can you lower the santee in the wall and run the new trap arm in front of the post?
Some dishwashers allow some room behind, do you have what you're installing on hand so that you could measure that?
I've been running my trap arms at 16" above the kitchen floor because of the new 10" deep sinks.

Going from copper to plastic, you will need shielded couplings that have sizing on the rubber sleeves for the two sizes.
Copper x PL
Thanks for getting back to me.

The dishwasher is listed at 24” deep per the spec sheet, but we have it still boxed up so I can open it to check if there is a space for plumbing.

However, if there is space at the bottom of the dishwasher, wouldn’t the sanitee be too low for the waste arm to make the connection? If I’m able to lower the sanitee could I drop it all the way below the plank flooring and run the waste arm under the floor in the joist bay, and have it come up under the sink? Or wouldn’t that create a siphon?

Would it be possible to install an AAV in the sink cab, in order to keep the vent height above trap weir, and then drop the drain into the floor? (The previous configuration definitely had the trap weir above the waste/vent opening it would seem?)
 

Jeff H Young

In the Trades
Messages
5,109
Reaction score
1,116
Points
113
Location
92346
by all means check your D/W measurements every D/W I've ever installed came very close to wall I've stripped drywall and notched in about halfway and generally fought with getting them to go in , but avoid dirty arms around D/W .
 

Massdiyer

New Member
Messages
4
Reaction score
0
Points
1
Location
Mass
If you go low and then have to bring it up, you will need to add venting. An AAV works for that.

What model dishwasher?
GE Dishwasher

Opened up the box to check. There is a ~ 4x6" space at the bottom rear of the unit that I might be able to route the waste arm through if I notch or move the non-structural stud. I think it'll be tight. If the slope of the pipe is too much where the weir is above the vent, I may still need to run an AAV. But at least if its run behind my dishwasher it would be easier to access it for maintenance or repairs vs. in the floor.

Sink 4.png
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks