Slip Joint P-traps?

Old 06-08-16, 05:30 PM
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Slip Joint P-traps?

In a post since deleted for rule violations a member contended slip joint P traps should never be used.
Source-National Standard Plumbing Code section and table 5.2.
ID for traps that service (kitchen/commercial) sinks shall be nominal pipe size 1.5 inches. P-trap for a basin/lavatory(bathroom sink)does not meet that spec. I have not seen a professionally installed p-trap with a slip joint installed on a sink.
Is this true?
Old 06-08-16, 05:55 PM
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I was a little confused by that response as well (since it was my suggestion) I'll let those more knowledgeable weigh in on codes, etc., but I've never owned a house that had a glued in trap for the kitchen sink. It's not like you can't get 1.5" P traps.....Of course you wouldn't use a 1.25 inch P trap for the kitchen. I don't see how that conflicts with the code language quoted.
Old 06-09-16, 06:24 AM
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That quote doesn't make a lot of sense. After 16 years, I've seen California homes plumbed like this:
about 75% slip tube traps, 20% ABS trap with nut, 5% glued ABS

Los Angeles requires special traps and there is no choice.
Old 06-09-16, 06:26 AM
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I agree with Paul. But I have had many customers come in telling me their traps have been glued together! I can only surmise that the previous installer had leaks and it was his way of solving them.
Old 06-09-16, 09:36 AM
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I do not consider myself a code expert in the slightest... but here's what I found (UPC):

1003.2 Slip Joint Fittings. A maximum of one (1) approved slip joint fitting shall be permitted to be used on the outlet side of a trap, and no tubing trap shall be installed without a listed tubing trap adapter. Listed plastic trap adapters shall be permitted to be used to connect listed metal tubing traps.
I don't see any reason that slip joint fittings would be prohibited (barring any local code amendments).
Old 06-09-16, 09:56 AM
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Thanks all. Was just wondering.

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