Waste Lines into floor drain

[Jerry Simon]

How do you all report homeowner-added fixtures, like this laundry tub, which purge into the basement floor drain. Clothes washer also empties into the drain, done as well by the homeowner when the washer was moved from its original location. In this city, I'm fairly sure the drain ties into the sanitary sewer system, not into a storm sewer system.

What's *bad* about this? Aside from saying it's unconventional, I reported lack of seal around drain lines, and potential trap/sewer gas problems.

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[Inspectorjoe]

How would sewer gas be a problem? You wouldn't get it from the sink or washer discharge, because it's only greywater. If anything, a regular flow into the floor drain will reduce the risk of sewer gas by keeping its trap from drying up.

The only bad things that I can think of are the floor drain not being able to take all of the water, the pipe being knocked away from the drain and the pipe on the floor being a trip hazard.

Here's my boilerplate: The laundry sink discharges to a floor drain. This is not a good practice. It is a trip hazard and can cause water damage to surrounding items. You should have a plumber reconfigure it to drain directly to the waste system.

[Jerry Simon]

How would sewer gas be a problem?

Because the laundry tub waste line isn't vented. The homeowner just stuck the tub waste pipe into the floor drain. The now-double-trapped line can cause the two in-line traps to be siphoned-dry simultaneously.

[Inspectorjoe]

Oh, you mean it's tied in directly. I thought you were describing what's very commonly done around here: the line is run across the surface of the floor and discharges onto the top of the drain grate.