Can I use the vertical wet venting on 5-stories residential building?

Hi Philo

I'm afraid that is a really loaded question here! A complicated question like this can really only be answered by your local plumbing inspector as each state has different codes/requirements and even then, if wet venting is allowed in a 5 story building it will need approval and your waste/vent design will also need approval from the LOCAL INSPECTOR.

When it comes to wet venting more than one bathroom off a wet vent you need to increase vent sizes and even then, your local inspector may simply say NO! *UGH*!

I'm afraid that is all the help I can provide you on this. Call your local inspector and just ask him. In this case, it will definitely save you time/hassles!

Mark

Frankly the whole idea is not a good one in the first place. Leads to lots of noise & slow carry out of the fixture. Certainly not in a multi-story building. Ever considered a product like a studervent ( air emitting valve .) they let air into the drain line while water is exitting the fixture & are approved in most jurisdictions.

Studer vents are not allowed in most codes. An AAV (air admitting valve) if allowed, must be accessible, if you are in The USA. Where are you located?

Five stories of wet venting, throw in some aav's, a little gas, a match, and once the smoke clears, start over with a licensed plumber.