It really depends how it was originally plumbed. If it was roughed in by a professional, you could possibly connect to it. But you would have to cancel the floor drain - meaning cutting off the drain and plugging pipe with approved plug.

The way you are thinking of doing it is the way plumbers used to do it all the time years ago. However, it is not up to current codes. If the vent for the floor drain is two inch, I would say yes, you could go for it, but know that it won't be up to code, and if you don't plug off the floor drain, you may experience backing up of washer water in the floor drain. Now, if you do permanently plug or cap the floor drain as Milo suggested, it would actually be up to current code, as long as the vent is not used for any other fixtures.

"Wet venting" a floor drain is perfectly acceptable as long as the vent pipe and drain portion is 3 INCHES OR LARGER. If the vent is 2 inches and you have no other choice, be sure to put a cleanout tee after the washer standpipe to auger the drain if clogs occur. There is no need to cut and cancel the floor drain, if anything the floor drain would now be equipped with a wash-out upstream. Important to be sure that what you are connecting to is, in fact, the floor drain's vent.

Curious, floor drains that are vented off a building drain. The building drain has a soil stack that takes drainage from fixtures. How does the floor drain being capped or plugged come into play to bring it up to code?

HI all:

Ahhh... that may be OK in your area PGH, but not in my area. You'll find that happens a lot on this site so we have learned to preface almost everything with "in my state" and "be sure to check local code requirements"... ;)

In my area, you can definitely wet vent a floor drain but you can't do it using a washing machine or a kitchen sink drain... no matter how much the pipe size is increased.

Are you sure they allow a washing machine to be used on a wet vented fixture... seems like the sheer volume/velocity of the water would siphon the PTRAP of the fixture, but then again I have never considered an increase in pipe size either. Let us know more, OK?

And not to step on any toes, but in terms of MGD77's and Milo's answer my guess is that they were not considering wet venting as an option here as their codes must not allow it either, but they did think capping/plugging the floor drain would be OK as long as a new PTRAP was installed above the floor. Seems reasonable... yes?

Finally, I would say to Herb that even if the vent pipe was only 1.5" you should be just fine as many states still allow 1.5" pipe for a washing machine. 2" is even better, of course. Install the PTRAP with a standpipe that is between 18"-30" for most states.

Back to you guys...

Mark

Thanks, massplumber. I belong to several other forums and understand there are differences as well as commonalities in plumbing codes. So to clarify, no stack venting floor drains? If no washing machines or kit. Sinks, what fixtures then?

Are you saying that if I have a single family home with 2 garage and 2 basement floor drains they must all be individually vented? Typically, if hydraulic grade allows, the floor drains can vent off a soil stack. And siphoning the floor drain?

Hey, if they stack vent floor drains in your area just say so and then it's up to the posters to consult their local codes or any of us to pop in and post what happens in our area. When we can, of course, we try to find out where the poster is from and give them the answer that is from the code book being used in that area.

In Mass, here's part of what my code book says on wet venting:

"Piping Not to Serve as Wet Vents. A waste and vent that serves a kitchen sink, a garbage disposal, a dish washer, or other fixture installed for culinary use, or one that receives the discharge from a clothes washing machine may not serve as a wet vent for any other fixture."....pretty much leaves sinks, toilet, tubs and floor drains...;)

Also, in my area, a floor drain needs a vent...can be vent stack within 8 feet, can be individual vent and can be wet vented using a drain/vent (as mentioned above), but a vent needs to be associated with the floor drain.

And finally, you asked about "siphoning the floor drain", right? Here, I was suggesting that the volume/velocity of water from a washing machine drain going down a floor drain vent is so great that it can siphon water or cause the drain to bubble/gurgle at the PTRAP and can allow sewer gasses into the home which is why, at least in my area, you can't use a washing machine to wet vent a floor drain...that's all.

Hope that answered your questions and hope you stick around and contribute...can always use the help, especially now that our "senior plumbing expert" (AKA Speedball) is down for awhile.

Thanks...

Mark

In my area, we have to vent floor drain with 2" dedicated vent. Vent has to have 2" clean out.

My area allows minimum 1 1/2 dedicated vent for floor drain(local plumbing inspector makes us have a DEDICATED vent for all floor drains. And we also are not allowed to have KS or washer on a wet vented fixture. Thanks Mark for clearing that up. That's the only reason I mentioned plugging the floor drain, but I'm sure it would work just fine without elimination the floor drain. LIke I said, we see it all the time with KS and washer both draining into the vent of the floor drain(old homes built by the government years ago). One area was an army base, and the other was a complete town relocation due to a dam being built. That's how they plumbed all them houses in those areas back then.