Shower Trap Installation

Hello Fellow Inspectors,
This is the trap for the shower drain. I have never seen it this low before. Should the trap and discharge into the main plumbing drain not be a little higher? The shower drain is the last fixture to drain into the main drain line but this doesn’t seem right.

It’s fine if your jurisdiction follows the international plumbing code. How long is the connection to the shower fixture? It should not exceed 24 inches. I’d like to see a hanger on that pipe as well as the building drain.

Looking at the hash marks on the 3” fitting I think it’s OK.

Thanks Martin, The connection to the shower is probably over 24 inches. I didn’t measure that. The main plumbing drain is well supported throughout its length, just not visible in the photo. The shower drain is not supported.

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I am not a plumber but is the trap in the pic lower than the main drain?

Maybe but I think it’s the angle of the shot that makes it appear lower. The hash marks on the 3” fittings looks good so I think grade is good.

Does your state follow the IPC? What state do you live in?

borderline, It looks like sewer water could flow into the trap.

It could if it jumped the bottom of the 3x1-1/2” wye into the 1-1/2” inlet. From the bottom of the wye to the shower inlet is about an inch.

Thanks for replying Scott. That was my concern from looking at it. That sewer water could back up into the trap. I am not a plumber either it just caught my eye. I also don’t know how full (how deep the water is) inside the main plumbing drain is if two showers are going and someone flushes a toilet.

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I am in Indiana Martin. They have been using a version of the 2015 IRC but I have read they just updated to the 2019. As for the IPC I can’t say. The county I live in doesn’t have a building inspector or require building permits. There is also an ejector pump right outside the house for the sewage. I wasn’t given any information about the ejector, whether there is a tank, how big, or anything else.

Yup your good to go. If the drain length to the fixture is over 24” that’s my only concern.

So a vent is not needed?

No it is not as long as it’s 30”-36” from the 3” drain. I forget which number is correct. IPC is kind of a crap code.

There is only one plumbing vent. It is in the main drain line under the master bath, the highest point in the main drain line.

I have noted that my house has a plumbing vent for the kitchen, and another near the bathrooms. I am unsure why some houses have 2 plumbing vents and others just one.

Some homes have a dozen vent stacks through the roof and some have one. A good plumber will tie all the vents together so that there is one penetration in the rear of the home. Of course architectural designs like vaulted ceilings throw a monkey wrench into a clean design.

I’d be recommending a check valve on that shower drain. If the street waste backs up into home, their shower would be the first place to fill with s_it.

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Well, I trust martins judgment. :+1: :grinning:

Thanks for the info Martin.

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The only time a check valve is recommended anywhere in a drain system is if the sanitary drain system is located below the manholes at the street. A lot of people don’t realize but on a slab house every drain under the slab looks like this. Same thing in their ceilings if the home is a two story.

Slab home …Oh OK.

All basements and check valves here in Massachusetts.