Install Double Bowl Sink Vanity w/ Only One Wall Water Pipe Connection & Drain Pipe Using PVC

DISCLAIMER: This video is not plumbing advice and was created for entertainment purposes only. The installation shown in the video may not meet your local code or any plumbing code. Do not use this video as a guide to attempt to repair or install plumbing on your own. Please consult a certified plumber for your plumbing repairs, and have all repairs performed to meet code.

We were remodeling the bathroom after the flooring was replaced in the house. After repairing all the drywall, we went shopping for a double sink bowl vanity for the main bathroom that previously only had a single sink, and therefore only one water and drain connection on the wall. We did not know that normally the plumbing needs to be set up in the wall for double sinks. Vanities are all so different, that you really need to select the vanity first, take measurements, and then do the plumbing in the wall.

We did not have time to wait, nor did we want to tear up our drywall after all that hard work of repairing it. It seemed possible to split the water and drain connections inside the cabinet. There was plenty of room behind the center drawers.

NOTE: An even simpler solution that would eliminate the need for the Air Admittance Valve would be to only use one P trap directly before the wall drain, and have both sinks feed into that one P trap. That solution appears to be permitted by code for up to 3 sinks as long as the sink drains are within 30 inches of each other. I thought about this prior to the current installation, but I was only thinking about using 1.25in bathroom sink drain components for the P traps, and there aren't any connections that allow you to T into that type of plumbing. However, if the P trap was instead made using 1.5in PVC (there are 1.5in PVC P traps available), and both sinks fed into the P trap using marvel to 1.5in PVC connectors and a T, then it would be possible. Then there would be no P trap under the left sink, freeing up more space for the shelf. The downside to the single P trap method is that there would be a long run of pipe before it reaches the P trap, allowing for more exposed surface area that can build up smelly gunk that is not protected by the P trap water. Bathroom sink drains can get an impressive amount of nasty build up on the walls.

Parts used for the connection:
- Air Admittance Valve AAV - https://amzn.to/3a6wCUg
- P Trap Kit, includes the marvel to PVC adapter - https://amzn.to/2KvPLV8
- SnappyTrap Bathroom Drain Kit - https://amzn.to/2KBl4h8
- 90 Degree 1-1/2in PVC Connector - https://amzn.to/3h1zCmr - Buy 1 of these if you have copper drain pipe at the wall. Buy 2 of these if you have PVC drain pipe at the wall.
- 90 Degree 1-1/2in PVC Connector Spigot x Socket- https://amzn.to/37rjZBy - This is for the lower connection to the wall drain if you have a copper drain pipe. You do not need this if you have a PVC wall drain pipe.
- Short Length of 1 1/2in PVC Pipe - https://amzn.to/2WtjyjO
- PVC Cement Glue - https://amzn.to/3h1yPBZ
- Hacksaw to cut the p trap kit and PVC pipes to length - https://amzn.to/3nyrL2f

Here's a link to the
0:00 Video Timeline
0:03 The Plumbing Problem
3:50 Drilling holes in interior cabinet walls
5:14 Test fit
7:59 Drain plumbing install
13:00 Water connections
16:30 Gurgling problem
18:00 Air Admittance Valve solution

#sink #bathroom #plumbing #drain

The products shown here were purchased by me with the intent to use them. I did not receive any free items, and I am not being paid or compensated for this review. The video and description may contain affiliate links. If you click on a link, I may receive a commission. Money earned helps to support my channel and bring you more informative videos about engineering, crafting, and DIY.