Shower has no vent

[S2igi]

Twenty-something years ago, I installed a bathroom on my second floor. Being young, and dumb I forgot to install any vent at all. The closest vent was where the 3" met the main stack probably a run of 15 feet. Here's the thing, I never had any issues and never thought about it again. Last year I renovated part of the bathroom and properly vented everything other than the shower (2" drain pipe, 1/8th slope). Due to its location a vent to code would be virtually impossible. The shower drain runs under the floor and in that direction the closest I could add a vent (vertically) is 8-9 feet.

Here's what I want to know, did I just get incredibly lucky that the bathroom fixtures all worked for more than 20 years without even a hint of trouble? I am well versed in the importance of proper venting but my thing seemed to work just fine without.

 

[John Gayewski]

What size shower head? The old 5gpm or more shower shower heads would likley have a different performance. With 2.5gpm in a 2 inch trap there might be some other factors that will cause a bad performance other than just venting.

 

[Sponsor]

 

[Breplum]

With low enough water flow down the shower drain, the top half of a 2" drain line is vented...esp. with your stated 1/8" per ft. slope.
That is some of the reason that "horizontal wet venting" has finally made its way into the UPC (I don't know the full story, but it is now accepted as science/truth, that half wet horizontal pipes vent well enough when stipulations are followed).
So, modern plumbing evolves and will continue to do so...then in a billion years the universe will collapse on itself and everything will cease to exist.

 

[Jeff H Young]

Certain things I dont mess with on code or at least go through a major inconvieniance to meet. 8 foot trap arm for a tub or shower is pretty risky to expect flawless function , but a lot of things work decent without meeting code and I dont want to encourage it but your guess is as good as mine as to whether the changes you are making will result in the same satisfactory results

 

[John Gayewski]

This would be of an oddity if a system was built to code and didn't function. Something built less than code can still function and there are probably millions and millions of code violations that don't cause a problem. Or maybe there is an issue that someone isn't aware of.

 

[Jeff H Young]

agree built to code good system not to code often functions good but hard to know if its going to function well