Schluter Floor Drain Product for Laundry Rooms & “Trap Primer” Drains
I was watching an episode of Matt Risinger’s in which he goes over old videos of his own home build and discusses how things worked out and what he’d change.
One of the items he would have liked to have installed (but wasn’t available at the time) is a Schluter floor drain that is part of their waterproofing system and is designed to go into laundry rooms to prevent flood damage in case of a washing machine supply pipe failure.
Risinger video – Schluter: Minute 32:18
https://www.youtube.com/watch?v=DivMTiA9U_k&t=133s
The other thing Matt mentions is that his plumbing inspector made him install a “trap primer” in the laundry room floor drain. This is a special drain trap that has a water supply pipe that feeds a small amount of water from a sink into the trap so that the trap never dries out and lets sewer gases into the house (Minute 33:18)
I’ve never heard of these. Apparently they are for drains that don’t have a regular amount of water moving through them. Has anyone installed one? If so, what brands are best?
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Replies
Rockies63,
Floor drains that don't have enough water regularly put down them to keep the trap filled can also just be topped up with mineral oil. Unless your code requires a self-priming trap, that's the route I would go.
I have a Schluter drain under my washing machine for this reason, but it doesn't have a trap (and therefore doesn't need a trap primer). It indirectly dumps into a different fixture's trap (think utility sink).
If the inspector allows it, the logical fixture to share a trap with the floor drain would be the washing machine drain.
Well, in my case, the washing machine inlet is naturally higher than the floor, and the trap is in the wall.
Part of my desire for the floor drain was also in the event of a clog on the washing machine branch (though I suspect if it ever gets used, it will be because of a leak).
I have a metal pan with an integrated drain under my main floor washer and a condensate overflow pan with drain under a HVAC unit in my Attic. Both drain lines have no trap and run internally through walls down into my basement where they terminate into a utility sink. The utility sink gets used frequently. I figure I’ll notice any water coming from either line and know I have a problem.
I have a homeowner that had a floor drain under their washing machine and a hose fitting started leaking. No one noticed any issue because the fast drip from the hose was just going down the drain. It was discovered when they complained to me of a musty smell in their laundry room and a higher than normal winter water bill. The washer/ dryer and adjacent cabinets did a good job hiding the moldy wet drywall. Turned into an insurance claim. So I worry if these emergency drains to the DWV system do their jobs no one will notice a problem. I ended up recommending water alarms place next to those types of drains.