Rough Plumb an Island Sink w/ a Bow or Loop Vent (check local code for your specific requirements) 

Thanks for sharing! Easy to pick at things and be critical, but those folks don’t get what your trying to do, I do and appreciate the awesome video.

Great job explaining the install!!! I have found that the two codes- UPC and IPC- vary greatly in some aspects. Everything you did in that example is contrary to the Uniform Plumbing Code, for those that asked you where you were from or questioned your install. You go off the International Plumbing Code which is very different than ours. Great explanations, but we (UPC plumbers) have to use the 45-90-45 method, we have to run the foot vent off the vertical, and are not allowed to go horizontal with a relief drain before hitting the wall. Also, we have to put a clean out in the wall of the foot vent. I'm happy to see plumbers sharing their knowledge. I take pride in my trade and I can see that you do as well.

OMFG I hate it when plumbers stub out PEX. Just buy the copper stub outs so they're solid. Goodness.

Awesome explanation

I agree with others that say that putting cleanouts on the loop vent would be very wise. Also, I wouldn't characterize the loop vent relief drain as a "feature" that keeps your sink from overflowing if it's main drain gets clogged. All venting should ideally be designed so that the fixture DOES overflow before water would get sent down the venting system. That's why they are to be designed so that the point that where the vent ties into the rest of the venting system is always above the overflow line of the fixture. Yes, having a fixture overflow makes a mess, but sending the backed up flow up the venting system and letting it drain out through the venting means that 1) you could have a fixture clogged for a long time and never know it because you never realize that the water is being diverted through the venting, and 2) during that time you could be draining debris through your vent system which it is not designed to handle, and then after you do finally discover the original clog and fix it, you may have a real mess cleaning the debris that ended up in the venting system. So it is better to just let fixtures overflow in general, because you are alerted to the clog right away that way. That applies to all venting, but would also apply to loop vents, with a couple caveats. When plumbing islands, often it is impossible to get the venting routed up above the overflow height of the sink. In that case you should get it as high as possible, definitely above the bottom of the bowl. That way, you can at least see water sitting up in the bowl when the sink drain gets clogged, even though it will never rise enough to overflow the sink because it will overflow the top of the loop vent first. Camo Matrix implies this is a nice feature of the loop vent, i.e. you don't get the mess of the overflowing sink, but you are still alerted that there is a problem because water is setting in the sink. I would say that the loop should 100% always be above the bottom of the bowl so you do get some immediate indication of a clog, but it is still better to get the loop above the sink overflow line if possible, because it is better to have the sink overflow than send anything down that loop vent if you have the choice not to. In the event that the loop vent is not above the sink overflow, the vent relief drain is really necessary, because without that, whenever you do send water down that loop vent, it will just pile up in there like a huge trap with no where to go, and completely block the venting, which again, you might never even realize after you unclogged the drain. (Actually even if the loop does go above the sink overflow, there is still the rare possibility with Murphy's law that you could created a situation where water could get sent down the loop vent line, so I would always put in a relief drain at the lowest point of the loop vent line.)

Very nice

Good job thank you!!!

Very interesting set up of PVC pipes you got there especially down in crawl space or underpart of the house. That emergency drain from the bow vent looks interesting. You must be down south or maybe SE. We do bow venting in MN for a island kitchen but we don’t do that emergency drain on the bow vent.

Where your bow vent connects to the emergency drain underneath, the water goes back the opposite direction through that wye... is that correct?

Why couldnt you put a p trap under the floor in the ceiling below and put a cleanout and bring 2 pipes up in the floor in the kitchen cabinet and back vent the drain and still connect it to the vent stack like you did? In toronto canada some inspectors dont allow loop venting so we do it that way

Someone asked if a P-Trap is still needed but the comment is now gone and I cannot reply to it so, YES, a p-trap is still needed under the sink.

Inland vent could've u used a san tee for vent then emergency drain going down through the san tee?

Island kitchen sink vent

You from WA?

Your piping is great, but those primer drips are killing me.

Were are the clean outS

Shouldn't use a why I'm a vent

Plumber here- you are missing the two clean outs on the island venting system/ piping.. Sorry. Also that connection between the vent and drain line is wrong and unnecessary.

That's not a proper loop/ bow vent.