# Do I need a vent on a basement utility tub?



## majakdragon (Sep 16, 2006)

Basically, if it has a trap and is tied into the main drain at any point, it requires a vent. If not, when using other fixtures, the trap water can be sucked out allowing sewer gases to enter the home. Many older homes I have seen with sinks in the basement were piped to a floor drain (with an air gap between the pipe and drain) and did not require a vent. This would be the place to use the AAV (Air Admittance Valve) if needed.


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## skipjack (Aug 15, 2008)

Okay... so... just to clarify, if I were to install a proper vent on the tub, I'd have to connect to the vent stack somewhere above the kitchen sink? In the attic maybe. 

Otherwise, an AAV on the tub is the way to go.

I don't know why I have such an aversion to AAV's... I guess the fewer moving parts, the less chance for failure.


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## TazinCR (Jun 23, 2008)

Your main vent stack serves two purposes 1. let air in to vent the fixtures which protects your traps. 2. Let gases vent to atmosphere. The AAV does # 1 and stops gases.


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## majakdragon (Sep 16, 2006)

Not in the attic, but above the kitchen sink. Look at the link (click on it) I have included. It has info on drains and vents and a rough diagram of a two story house with a basement. It shows how the drains and vents are installed.

http://www.hometips.com/hyhw/plumbing/74drain.html


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## TazinCR (Jun 23, 2008)

Check this link
http://www.rectorseal.com/index.php?site_id=1&product_id=100


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## skipjack (Aug 15, 2008)

Thanks guys. Once I get the cabinets torn out in a week or two, we'll see how much room I've got to work with fitting a vent for the tub. I'm thinking I can slide a pipe down from the attic through the original hole, attach a "Y" connecter for the vents through the hole in the drywall made by the previous owner, slide my drain pipe and vent pipes up from the basement, connect it to the "Y" and then pull the whole assembly up from the attic until the joint is above the level of the sink and then attach the drain pipe and vent in the basement. 

Boy... sounds pretty easy when I write it down like that. 

Is there any restriction to the number of bends a vent can take on it's way up? I may need to put a turn or two to get it over to the actual tub drain.


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## EAP (Aug 27, 2008)

I did not look at the diagrams linked in the posts above.

That said, the vent tie-in must be at least 42 inches above the flood rim of the highest fixture on the drain.

If Air Admittance Valves (these are NOT mechanical valves) are permitted by code in your area, why rig up a rube goldberg vent contraption that is costly and wastes time? The key is to be efficient in design as well as function.

AAVs when installed per the manufacturer;s instructions normally perform well.

If the original utility tub was located in the vicinity of the vent stack, it borrowed its venting from the stack, similar to floor drains.

You may wish to get a good plumbing book and there are plenty at your local library or Home Improvement store. And at the very least, "consult" a local plumber.


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