Venting questions in new basement bathroom

virtualo

Is this the right amount of vents? Or too much.

Any other suggestions appreciated.



This was the original design, that I changed... See revised pic below




This is the revised plan.... I added a sink and a few more vents....

al's sewer

only thing I would have done different is i would have ran 2 inch pvc to the tub if this is underground plumbing and reduced it to 1 1/2 inch at the inlet side of the trap other than that it looks good to me.

Bob Mariani

Even the sink vent should be 2".

virtualo

OK, thats ok,,, I have the pit and the trench dug up. But have not laid pipe yet... So not too late to change pipe sizes....

So your saying 2" minimum pipe sizes for under concrete?

So the bath and sink sould be 2" pipe?

And all the vents should be 2" also?

al's sewer

Yes al lines under the slab should be min. 2 in. The vent on the sink is ok to be 1-1/2 since that sink is the only thing your venting tub vent can be 1- 1/2" also since you have a 2 inch vent on the toilet but it wouldn't hurt to be 2 in. your vent for the pump should be 2 in all the way thru the roof with nothing else tied into it. all the other vents can tie in together in the ceiling with 2 in going all the way to the main vent stack above the last fixture or thru roof. This can vary depending on your local codes so you might want to find someone in your area that is familiar with the codes.

al's sewer

You could actually eliminate your shower vent as long as you leave the 2 inch vent on the water closet and your shower is within 4 ft of the water closet. but you can leave it in if it makes you more comfortable.

mpgumm

for sure do not do any less than 2" Drain under ground on any fixture. The rule of thumb when doing under ground the bigger the pipe the less chance of any clogging problems. Here in Chicago, it is code that any under ground pipe be no less than 4"- that is because once it in the ground- you do not want any problems. That is why there is usually not clogs or back ups. And on a toliet do not use anything less than 2" for the vent. On other fixtures 1 1/2" is o.k for vent. When you do under ground do it so you will never have to cut concrete and did to get to something. Clean outs are also a good Idea.

jogr

I'm surprised your vertical basin discharge pipe is 3". I thought those were usually 2" till they tied into the 3 or 4" gravity drained horizontal portion of the system. Won't a 3" vertical discharge pipe hold a substantial volume of waste that will drain back into the basin when the pump shuts off?

HABSFAN2006

I have the same setup, with this pump, 3" discharge and 2" vent, It works great 100%, and I would say this is the best way to do it.

You do need a one-way valve three feet above floor level with a screwed on connection. this will ensure not the whole pipe will empty everytime, only under the valve.

another important point is to drill a 3/16" hole in the pipe in between the pump and before exiting the container. this will help empty the pipe at the cycle's end, and will help avoid any possible air locks in the pipe.

al's sewer

you are right they are usually 2 inch but the 3 inch will be ok as long as there is a check valve installed with 3 feet of the pump.

Bob Mariani

That would leave 5 feet or more of 3" pipe full of water. When the pump cycles will it still push this left over fluid out? I have read so many different opinions about where to place a check valve, as well as which one is the best type to use.

HABSFAN2006

yes, I can confirm I have this setup with 5-6 feet of pipe above the valve,
and this works fine. Now, the pump rating comes to mind, and I know it is rated roughly double the pump height i am using for.

A standard 1/3" hp sludge pump might not be able to do this.

mpgumm

just curious, how come you are using a 3" ejection line coming off the pump? Usually, it is 2" with a check valve, the two inch is connected to a 3" or 4" waste line. Not sure if your pump will have a 3" outlet. Just haven't seen it on house sewage pits. As far as the vent 2" is correct.

kenmac

Just to add. I've never installed or seen 1 with a 3" discharge.. Only 2" what size is the discharge outlet at the pump ? Did you increase from 2" to 3" ?

virtualo

Here is a link to the system I have: http://www.lgpc.com/Product/ItemDeta...?ProductID=944

It has a 3" discharge straight out of the pump.... I figured, the bigger the better!!!!