Dual sink with garbage disposal install

Nicole40December 14, 2011

My husband installed a dual sink with the garbage disposal on the pipe side. Dishwasher is on the left side. Are the pipes and hoses set up correctly?

Is the hose from the air gap to the garbage disposal too long? Should it look more like the blue line? Should the dishwasher hose sit more like the red line?

Should the pipes have been set up like blue lines?

Here are closer pictures of the �junction� above the trap:


Thank you for reporting this comment. Undo

The drain line from the dishwasher is fine but I see three code violations on the sink & disposal drain lines.

1. The two drains are connected by means of astandard sanitary tee. Code requires a baffled tee.

2. The P-trap is too low, which resulted in installing an 1-1/2" vertical offset on the fixture arm. Code requires a 1/4" per foot downward pitch from the trap weir to the vent.

3. No cleanout. Code requires a cleanout on the upstream end of all drain lines. If you have a removable trap removing the trap will serve as the cleanout but when the trap is glued in you must install a cleanout on the line.

I can certainly understand why he installed the unit in that manner, but there is a much simpler solution.

First off, get a "disposal type" end waste or center waste kit. When installing a disposal type kit you begin by discarding the 1/4 bend (90 deg elbow) that is supplied with the disposal unit. The disposal type waste kit will have a cross tube that has a flat flange on the end. That tube is then installed on the disposal in the same manner as the 1/4 bend, but the line will no come away at the same elevation as the disposal discharge port. You then shorten the length of the tailpiece on the opposite sink and connect the two lines together with the "Baffled Tee" that is supplied in the disposal waste kit. In this configuration the tee is higher permitting the P-trap to remain at the correct height to provide the required pitch to the fixture drain line.

In the configuration in the photos it would probably be best to install a disposal type center waste kit. This would then put the tee midway between the two sinks.

You would then have to cut the fixture arm near the wall and install an 1/8th bend (45deg sanitary elbow) and extend the fixture arm out towards the center where it will meet the P-trap tail piece.

It is important that you extend the fixture arm from the wall to reach the trap. Code prohibits adding an extension tailpiece on the P-trap.

I have prepared an illustration that will show you how the disposal type kits are configured.

    Bookmark   December 15, 2011 at 2:55AM
Thank you for reporting this comment. Undo

From your pictures, the new P-trap goes at the bottom and extends to the wall?

    Bookmark   December 15, 2011 at 5:01PM
Thank you for reporting this comment. Undo

Yes, the tailpiece from the tee can be cut to the appropriate length to fit the input of a P-trap

    Bookmark   December 15, 2011 at 5:38PM
Sign Up to comment
More Discussions
Supply lines above subfloor, what are my options?
I am installing new floating vanities in my 2nd story...
Under counter water filters…again
I've lurked here for over a year and have learned so...
Fleck 5600SXT 64k Setup
Well I recently had a new water softener installed...
Water Softener - calling justalurker
Hopefully you are still around. I had reached out a...
Help with smelly well water
Just a little background. We bought a house 3 years...
Sponsored Products
Modern Bean Bag The Pear Bean Bag Chair In Black
Beyond Stores
Polaris P306 Taupe Ensemble Chrome/Hardware
Small Corner Stainless Steel Bathroom Sink By MaestroBath
24" Napa Vessel Sink Vanity
Signature Hardware
Berkeley 72" Double Bathroom Vanity by Wyndham Collection - White
Modern Bathroom
WhiteHaus Reversible Series WHQDB332 20 in. Double Basin Farmhouse Sink - WHQDB3
$985.35 | Hayneedle
Porcelain Vessel Sink
MR Direct Sinks and Faucets
Indoor Area Rug: Senses Shag Red 7' 9" x 9' 9" Plush
Home Depot
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™