below slab floor drains

AK_Todd

Couple questions on floor drains. I've seen that a siphon can develop if your pipe extends too far past the p-trap without venting. I know there are lots of such drains without vents so is this really an issue or is there a special fix.

For those floor drains in the middle of the garage or in the mechanical room, do they need cleanouts? I ask because I've seen several drains with no cleanouts. I have seen drains with the a cleanout passage (that go to the other side of p-trap) in the side of the drain bowl. Other than one of these drains or a whole-house p-trap, what options do I have for small (2") floor drains clean-outs?

Zman

Venting

Drains in the middle of slabs are required to be vented. The vents branch off close to the trap and go to a nearby wall. There are commercial traps with cleanouts. Why do you need one? Zurn makes quite a few. Plumbing waste and vent is pretty involved. It is not something you learn quickly.

Hilly

in Canada..

Up here a 3" P-Trap could be as far as 12' from its drain connection and not require a vent.

kcopp

Here is one....

solution. All in one.

http://www.siouxchief.com/products/drainage/residential/floor-drains/weldone

Hilly

still needs vent

That is a 2" drain which means that there will be a vent take off required within 8' of that in some form, be it individual, wet....

icesailor

Trap to vent distances:

In MA, a 2" trap outlet can't be more than 6' developed from a vent and 3" is 8'.

Minimum drain size under a slab is 3" with short runs of 2" allowed.  You can "Wet Vent" a floor drain trap/drain with a sink drain, tied in closely to the trap where waste water from the sink will splash over into the FD trap so you won't need a trap re-sealer.

If the trap is in a garage, it is supposed to rum through a oil and gasoline interceptor.