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Boca Vent for basement plumbing

Truckie1's picture

I've been thinking about adding a bathroom to my unfinished basement. After reading the article in the latest Finehomebuilding I'm even more eager.

I have an old house with mostly cast iron plumbing with only one 4 inch vent. I'm going to have to install an ejection pump because my sewer line leaves the house above the basement floor level. I have no common wall to run a vent. Would it be a bad idea to install a boca vent for the basement system?

I'll have a toilet, shower, vanity, washing machine and most likely another sink for this system. If a boca vent will work, what size should l use?



(post #81188, reply #1 of 6)

boca vent???  OK - I give, what's that?  Maybe some kind of local jargon for a AAV (Air Admittance Valve) also known as a Studor vent?

If it is an AAV, first you need to find out if AAVs are even allowed by your local/state/whatever code and secondly you need to verify that your local code officials allow them.  Next, that's a lot of fixture units to put on one AAV...

There are other guys here who can be more specific.


(post #81188, reply #2 of 6)

This guy has a Q for you...


(post #81188, reply #3 of 6)

The problem is that system with a hold tank and sewer ejector pump won't work with an air admitance valve (Studor valve).

When "stuff" is flowing into the tank you need to let air out. When pumping out the you need to let air in. An AAV will only let air in.

That said I have heard that SaniFush does make one that can work without extra venting.

I have not seen the instruction for it so I am not sure how it works. One way would be that the pump always comes on the instant that any "stuff" flows.

Another would some kind of check valves and may solenoid valves so that it can use the discharge line for venting out during the tank filling and an AAV for when pumping out.

A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
. William the Geezer, the sequel to Billy the Kid - Shoe

(post #81188, reply #4 of 6)

I have no idea what a "boca" vent is.

Like other have stated an air admittance valve will not work on a sewage ejection system.

While it does not meet code you can run a parallel line to the pumped waste & tie it in to the top of the waste pipe upstream of the pumped connection. This will provide a place for displacement of gas as the tank fills up. With this set up you will need a couple of AAV's to let air into the system so the pump does not create a vacuum on the secondary pipe ran to the waste line.

“The world is a dangerous place, not because of those who do evil, but because of those who look on and do nothing.”Albert Einstein


(post #81188, reply #5 of 6)

Just for referneces BOCA was a one of the groups that publised a buiding codes.

"Building Officials and Code Administrators (BOCA) (published the BOCA National Building Code and other National Codes) is now the International Code Council. You are being redirected to the International Code Council website. In 2003, more than 190 years of combined building and fire safety code development and 30 years of anticipation for one organization to produce codes for use across the country and around the globe became a reality when BOCA, ICBO and SBCCI consolidated to become the International Code Council."

Don't know if that was the name of the or not. Might have ben the UBC.

A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
. William the Geezer, the sequel to Billy the Kid - Shoe

(post #81188, reply #6 of 6)

Oh sorry. I'm apparently not up on my plumbing lingo. AAV is what I think I'm inquiring about.