Ask Me Help Desk - P trap Tub overflow

Hi,

I am installing a tub in a new construction and the drain didn't work out right, but I did manage to get it hooked up , but due to residents of the location I couldn't get the overflow piped in. (to get the overflow in I will have to jack hammer out the floor)

So I have a few questions.

1. Is an overflow required?

2. I have a vent that I could easily hook it into, but I am concerned about sewer smell.

2a. I am planning on putting it into the vent with a P trap, but I am concerned with it losing its prime, due to the fact it is an overflow in a spare bath, should this be a concern?

2b. Is there an alternative to a P trap that allows water to flow out but not let sewer gas flow back, but doesn't require water to work (a reed valve or duck bill valve) that will be accepted by a plumbing inspector.

THANKS,

K

Sorry Grump but it sounds to us that you made a critcial error when you placed your drain to begin with. The drain should have been in the wall along with the trap. Your tub overflow and drain terminate a few inches outisde the tub foot print. #1 yes #2 don't do it #2A losing its prime?/ what prime do you mean, are you talking about the water trap? #2b check with your building inspecter, I think you will not be happy.

Thanks for the reply Ballengerb1.
The Prime I refer to is the water in the trap. ( I kind of mispoke, I wasn't going to tie into the vent without a trap, I am a little slow, but I know better than that).

Regards,
K

Speedball1, Tom, will be along shortly and maybe come up with a way to save you some time. In the meantime call your inspector, codes vary from place to place and maybe he can tell you what is allowed. For example I have 2 homes, AAVs are allowed at one and not the other, one place requires a dishwasher air gap and not the other, go figure.

Quote:

Originally Posted by Grump365

Hi,

I am installing a tub in a new construction and the drain didn't work out right, but I did manage to get it hooked up , but due to residents of the location I couldn't get the overflow piped in. (to get the overflow in I will have to jack hammer out the floor)

So I have a few questions.

1. Is an overflow required?

2. I have a vent that I could easily hook it into, but I am concerned about sewer smell.

2a. I am planning on putting it into the vent with a P trap, but I am concerned with it losing its prime, due to the fact it is an overflow in a spare bath, should this be a concern?

2b. Is there an alternative to a P trap that allows water to flow out but not let sewer gas flow back, but doesn't require water to work (a reed valve or duck bill valve) that will be accepted by a plumbing inspector.

THANKS,

K

Grump,
We got to get together on terms here.

Quote:

I couldn't get the overflow piped in. (to get the overflow in I will have to jack hammer out the floor)
So I have a few questions.
1. Is an overflow required?

A tub waste and overflow are installed together ,(see image) and you don't have to jackhammer anything to in stall it. Could you be referring to a vent? If not please explain?

Quote:

. I have a vent that I could easily hook it into, but I am concerned about sewer smell

If you tie in downstream from the trap there will be no odor. That's what traps are for.

Quote:

I am planning on putting it into the vent with a P trap, but I am concerned with it losing its prime, due to the fact it is an overflow in a spare bath, should this be a concern?

Now you got me! Overflow in a spare bath. Are you saying that you have two tubs connected to the same trap? You use the word overflow a lot. Please explain what the word means to you.

Quote:

2b. Is there an alternative to a P trap that allows water to flow out but not let sewer gas flow back, but doesn't require water to work (a reed valve or duck bill valve) that will be accepted by a plumbing inspector

Mechanical traps are illegal in every set of codes. Why would you ask? What's going to suck the water seal out of a "P" trap?: Grumpy, You have a situation here and you haven't explained it too well. Your questions just generate more questions. Would you care to start over
And try again? Regards, Tom

Let me try to clear this up, When the trap was roughed in (under the foundation) a tub box was placed (plastic box full of dirt to keep the concrete from forming around the trap) something got off (a measurement or whatever was wrong and the tub trap with stub out was shifted to far back(towards the middle of the tub). So Now I have a mess, I managed to make up the tub to the drain, but the concrete is poured in such a way that it doesn't allow the overflow (The pipe to allow excess water out of the tub (not a vent)) to meet with the drain fitting, SO I now have a tub piped to a drain (and a trap) without an overflow.
( showers don't require overflows so I was hoping maybe a tub wouldn't)

The piping worked out so a Vent (a sewer vent allowing water to drain) is accessible, and would be real easy to tie into (with a trap of course) but to get water in the trap to do its thing, you have to fill the tub to the overflow (no problem) this would theoretically work and perform fine, but I am worried that the bathroom won't get enough use to keep water in the vent. SO I was hoping for a reed valve or duck bill valve that would allow water through but not let gas back up to be installed in line with the overflow drain (and not interfering with any other vent piping.

If I wanted to pipe the overflow like it would typically be piped in to the main tub drain I would have to chip out the tub box to allow room for the pipe to get down there, an option I Really want to avoid. ( I tried a BIG Sledge and made very little progress)

OH YA, The concrete guy managed to pour THICK concrete under the tub box and I have a concrete beam somewhere real close into the mix.

Thanks,

Grump