Slip Joint P-traps?


Old 06-08-16, 06:30 PM
ray2047's Avatar
Thread Starter
Join Date: Mar 2006
Location: USA
Posts: 33,583
Received 13 Votes on 11 Posts
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?
Sponsored Links
Old 06-08-16, 06:55 PM
Join Date: May 2015
Location: USA
Posts: 3,138
Received 2 Votes on 2 Posts
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, 07:24 AM
Handyone's Avatar
Join Date: Aug 2000
Location: U.S.
Posts: 5,450
Received 0 Votes on 0 Posts
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, 07:26 AM
Norm201's Avatar
Join Date: Sep 2013
Location: United States
Posts: 9,184
Received 255 Votes on 229 Posts
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, 10:36 AM
Forum Topic Moderator
Join Date: Sep 2005
Location: USA
Posts: 5,408
Received 128 Votes on 119 Posts
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, 10:56 AM
ray2047's Avatar
Thread Starter
Join Date: Mar 2006
Location: USA
Posts: 33,583
Received 13 Votes on 11 Posts
Thanks all. Was just wondering.
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: