Possible S trap

Looking for input on this sink drain configuration. Looks like an S trap to me but wanted to confirm I am looking at this right.

It looks fine, Justin. :smile:


about all they could do without putting a hole in the bottom of the sink base…

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Yes, I understand why they did it but was not 100% sure on S trap or not. Thanks for the input guys.

nothing to mention in my opinion Justin…

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It’s wrong, the trap weir should not be above the vent opening, this can allow siphoning of the trap’s water seal.

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Can you help me understand what you are saying, Simon?:

Is this what you mean?


Look at Aarons image, hopefully it will help :slight_smile:


I had one exactly like that n an older home that I lived in and never had a problem with siphoning…but, alas, I suppose it can happen.

Thanks, Aaron… :smile:

OMG Larry! you sound like a seller :sweat_smile:

You may not have realized… and reprimed it before it became noticeable. It also typically only happens when you fill the sink up and pop the drain. You did call out s-traps, right? they also don’t always siphon and can cause no problem for 100 years depending on their use :slight_smile:

I was back on that 8th house.

…and I did call out what I thought were s-traps. Learn something every day over here. :smile:

Great explanation, Aaron

Yup, Joe, Aaron’s on the ball. :smile:

I was actually asking for confirmation because I too was learning something! :rofl:

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That is 100% an S trap

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Are you kidding, Martin? :joy: :sunglasses:



Prove me wrong.

The trap illustrated by the poster

goes one they further with an extra change in direction.