strap or p trap

[cory nystul]

I found this today but i am unsure if its a p or s trap. I have been researching and found contradicting info.

Can somebody please explain. Thanks much.

30759

[Rick Cantrell]

Because there is not a trap arm, it is an S trap.

Also trap allowed is between 2-4"

[Jerry Peck]

Neither.

It looks to be what is called "crown vented" - the minimum trap arm length (as I recall) is two times the pipe diameter, that looks to be shorter than that.

The definition of crown vented is slightly different than the above, but the above is close.

[Rick Cantrell]

Neither.

It looks to be what is called "crown vented" - the minimum trap arm length (as I recall) is two times the pipe diameter, that looks to be shorter than that.

The definition of crown vented is slightly different than the above, but the above is close.

I mis spoke, thats what I was thinking of. Thanks for reminding me.

[cory nystul]

I mis spoke, thats what I was thinking of. Thanks for reminding me.

I must admit i am completely oblivious of a crown vent. Is it acceptable? what are the upsides and downsides to this kind of vent. Should it be called out in a report?

[Rick Cantrell]

I must admit i am completely oblivious of a crown vent. Is it acceptable? what are the upsides and downsides to this kind of vent. Should it be called out in a report?

This shows a crown vent (p19)
http://www.plumbingpros.com/pdf/dwvents.pdf

[Rick Cantrell]

Another example
http://www.ilga.gov/commission/jcar/admincode/077/07700890ZZ9996deR.html

[cory nystul]

Thanks to all. It very much confirmed what i thought as well as giving me more information to learn to help improve my inspecting skills. Thanks!!

[Ralph Holden]

As said in 1st reply, the maximum trap seal is 4" deep. That's measured from the top of the return bend on the bottom of the trap to the weir (where it overflows into the (too short) trap arm). This one appears to be more than 8" deep.