I have a floor drain that sits in a tiled area that runs 12-15 feet the entire width of the utility room. There is a lip to hold potential leaks from mishaps with the washer and water heater that sit in the containment area. The house is raised as are many in the metro area.
The first time I crawled under the house, I discovered that the drain just goes into the crawl space. I's day it is 2" PVC. It is not a real problem from a water standpoint. The trouble is that it is a rather large air leak and I am trying to seal the house up. It is really low-hanging fruit for air sealing. I would like, however, to keep the drain functional.
There is a surface drain catch basin/grate nearby on the outside that currently accepts water from a downspout and condensate from AC units. It is oversized. Is there any problem with my installing a p-trap and running a line to the grate?
I'd have to remember to fill the trap periodically, but that should not be too hard, especially if I float some mineral oil in it. I might have to install some make-up air for the dryer after I get the place sealed as the drain is probably what is providing it now.