Uh oh. P-trap for washing machine drain is below the floor.


Old 01-11-14, 09:31 AM
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Uh oh. P-trap for washing machine drain is below the floor.

I was doing some repair to some electrical and had to remove a large section of drywall near my washing machine drain. I discovered that the P-trap was not even in the stud cavity above the floor. The washing machine line actually drains down below the house (pier-and beam house) and into a common P-trap below the floor. I am pretty sure that code states that the P-trap should be above the floor, correct?

Here is my dilemma. I have never had any problems with the washing machine drain ever. For me to bring this up to code, I would have to put a P-trap above the floor and also a new vent pipe going straight up through the roof. That's a ton of work, plus the location of the new vent pipe would be blocked by an attic furnace.

Bottom line. Headaches, big time problems if I go about this to try and bring this up to code. Seeing that there are no problems with this now, should I just close up the drywall and not worry about it?
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Old 01-11-14, 10:22 AM
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mike can confirm code. I have worked on many newer houses where the trap was below the floor, but still above the main drain. Unless there is a local thing, why do you have to bring it up to code? You were working on electrical, not plumbing.
Old 01-11-14, 11:44 AM
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Codes are constantly changing so houses are generally required to meet the codes in affect when the home was built. Following that thought you would be grandfathered in. The sticky part is that some localities require that any renovations or repairs be done to meet current codes. If the wall was opened for electrical work and you saw the plumbing then you're probably OK though getting closer to a gray area.
Old 01-11-14, 07:20 PM
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As I understand it, current UPC states that all traps need to be above floor level (other than tubs/showers). This can be overridden by local codes.

But I agree with Pilot Dane and Larry, unless there's an issue with it (which you mentioned there isn't) or an inspector makes you, I don't see any reason to change it. It's not particularly unsafe or other issue that you should change.
Old 01-15-14, 06:22 AM
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My washer's drain trap is under the floor. So is the trap for my water softener drain. Passed inspection four years ago without a problem. Code here is IRC.
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