View Full Version : wet venting no-no?

11-13-2004, 11:57 AM
So we want to add a bathroom in the attic right above an existing bathroom with the main stack easily accessible. I know the right way to do it is to cut into the main stack below the existing bathroom and run a drain stack parallel to the main, joining them below to avoid wet venting a bathroom.

Question is - since we're a few weeks from having a baby we don't want to start ripping apart our main bathroom to do this right. Assuming we will (and I swear we will) correct the drain plumbing later, what would happen if I simply wet vent the attic bathroom for the next 2 years or so? Likely we would use the bathroom about 40 times per year (mainly when the in-laws come to visit and stay in the attic guestroom).

Basically I need to know what problems (other than code compliance) might arise from this situation. Given reduced use, could we get away with it for some temporary period? Other thoughts on how to make this happen with the least construction debris impact (remember the baby is coming...)

Thanks, Matt

11-13-2004, 01:10 PM
The easy answer is that once you install the plumbing for that bathroom, it will be almost impossible to redo it properly. At least for a reasonable amount of money, since you would have to redo a lot of the lower level piping, and also install a new vent past the new bathroom for the lower level venting. Sorry, but your promise may have to be made with your fingers crossed.

11-13-2004, 01:50 PM
hmm, I had planned to gut the old plumbing when we redo the lower bathroom in 2 years, so maybe that helps address your issue? And other than the financial expense, would I have any issues with function (ie. smells, backups, etc.)?

It would seem like I could be smart to run a seperate (new) vent stack for use later on when I redo the lower bathroom. If the vent piping is already in place and just sitting idle behind the wall I can tie right into it....

I would be able to tie in the lower vent to the main stack before exiting the roof, or do I need a unique roof vent for each stack in this case?

thanks again, Matt

09-17-2008, 04:54 AM
As I understand what your want to do, you will not be wet venting the new bathroom, you will be wet venting the lower bathroom, which is what is not allowed. You will be running waste from the second floor down past were the vents for the second floor fixtures tie into the stack. You risk waste going into and clogging those vents. Then you will have issues of trap siphonage.

Most of us are pretty friendly to DIY projects. This is a case where we have to urge you not to do it wrong. It will never get fixed, without throwing a lot of money at it. Somewhere down the road, when you have moved and the plumbing will be acting up, the new homeowner and his plumber will be scratching their head...."can't figure out why these vents don't work". Your handywork will be boxed up in the walls, and nobody will ever know!

I do have a solution for your inlaw visit: MOTEL 6. Tom Bodettt has the lights on for you! Seriously. This is how we handle family affairs, both on our end , and the other end.

09-17-2008, 07:19 AM
I'm just kinda wondering why you would go ahead and do something that you know is wrong and then find ways to justify it? We could all spend each and every day doing things the wrong way and make excuses for it but then, why bother with the code or a license? I know the answer is always, " I can't afford it" or " I don't have the time" and a million other excuses as well.
Here's the rule. If you can't do it right, Don't do it at all.

That said I'll bet 5 bucks you go right ahead and do it anyway.:(

09-17-2008, 07:24 AM
Plumbing from the Latin plum bum for lead is the skilled trade of working with pipes, tubing and plumbing fixtures for drinking water systems and the drainage of waste

Is a "plum bum" a plumber dressed like the "Fruit of the Loom" guy? And who are you calling a bum? Or did you intend to type plumbium and hit the wrong keys.

09-17-2008, 07:30 AM
Plumbum comes from the latin Plumbarius which means one who works with lead. Plumbarius was later shortened by the Romans to Plumbum.

What does any of this have to do with the thread?

09-17-2008, 11:27 AM
Plumbum comes from the latin Plumbarius which means one who works with lead. Plumbarius was later shortened by the Romans to Plumbum.

What does any of this have to do with the thread?

It was just a spamer posting a link to a website...

09-19-2008, 07:04 AM
Plumbium Worker Worked with plumbium (lead) - a plumber. from the Latin, plumbium = lead

09-19-2008, 07:20 AM
So, what do you suppose he did about his bathroom problem? :D

09-19-2008, 02:20 PM
oops! just noticed that this thread is from 2004....

09-19-2008, 06:14 PM
Harry revived it when he posted his spam link...:mad: