Floor Drains do they require trap venting?

[deepstuff]

Hi,
Just pouring slab and setting up two floor drains. They are all-in one units with traps and back water valve built into drains. They will run to just outside my slab and dump into a below grade pit or french drain. Do I also need to run a vent line for trap venting?

 

[Cyberbear]

From my limited experience venting is to prevent sewer gasses and smells from entering the living environment. Some venting needs are difficult to accomplish but necessary. You may wish to consult with a plumber or the building dept. for exact answers.

 

[Bondo]

Hi,
Just pouring slab and setting up two floor drains. They are all-in one units with traps and back water valve built into drains. They will run to just outside my slab and dump into a below grade pit or french drain. Do I also need to run a vent line for trap venting?

Nope,... shouldn't be necessary,...

 

[CNGsaves]

^ ^ ^ Ayuh . . . . . what Bondo said !!!! Normal drain in Canada if no rules.

 

[cdestuck]

Same as the drain setup I have in my garage. Two drains hooked together running outside the foundation into a bunch of shale along foundation. No traps, no vents, all is good.

 

[srleen2]

Only needed if you're gonna be ******* in it or taking dumps in it

 

[Radix2]

If the drain is just going to terminate outside, you might consider a trap just to stop air from blowing in and out of your building through the drains. Not an issue into a closed dry well, but might be if just flowing into a pit.

 

[sublimate]

If the drain is just going to terminate outside, you might consider a trap just to stop air from blowing in and out of your building through the drains. Not an issue into a closed dry well, but might be if just flowing into a pit.

I'd also put in a trap to stop, or at least hopefully slow down the creepy crawlies coming in thru the drain.

 

[pmiranda]

I think you only need a vent if there's a trap to cause a vacuum to form when water goes down the pipe. If you're just draining to outside you don't need either, except for the aforementioned cold air and creepy crawlies.
A separate, but related issue is a grease trap to keep bad stuff from plugging up the drain or going out into the ground and polluting the well water and killing your plants.

 

[rsanter]

Check your local rules...but

If it drains into the sewer then you need a P trap

If it drains to an dry well or just open ends to somehwere outside, then no P trap is needed

Bob

 

[James E]

I'm with the guys suggesting that it might help to keep snakes, bugs and mice out of your garage.

 

[Thumper68]

I put a trap on mine for the afore mentioned reasons, keep the cold and critters out. No vent.

No vent, if enough water is going through to fill a 4 inch pipe I have bigger issues then not getting good flow.

 

[rburke65]

I would think that NO trap would be required.

 

[padroo]

Those cheap PVC floor drains are built so they hold water to form a water seal but you would have to pour water down them every once in a while to make that feature work.

I have two garages with floor drains and I wish I never put them in. One because the floor is not level there and a creeper gets caught. I can't put a ramp or jack or jacket and in that area. The house garage has one and in 19 years has never been used.

 

[rancherbill]

Not needed, but as mentioned mice, bugs etc. The most important thing is Freezing temperatures. It's nice to have a trap, but the water might freeze and crack the pipes.

My drain has no trap, the pipe goes from the house to a dry well made of geotech fabric filled with gravel. The pipes are protected by a frost box. A frost box is an upside down 'U' made of Styrofoam.

 

[alberto]

I'm assuming the correct answer to this varies according to location/code. I asked a licensed plumber this question about a year ago, and was told that venting is required for floor drains. I'd ask locally.

 

[Radix2]

I'm planning on floor drains for my build, 8 feet back from the doors and centered in the openings (under the parked vehicles) - rectangular space at each bay sloped to the drain the rest of the floor flat. There is separate space for work, so no issue with creepers.

How does this plan sound ?

Anyone know of some nice drain assemblies to use ? I think I want a decent size one with a sump for mud, etc. that can be easily cleaned.

 

[Mr onetwo]

I'm assuming the correct answer to this varies according to location/code. I asked a licensed plumber this question about a year ago, and was told that venting is required for floor drains. I'd ask locally.

That is correct only if you are hooking to a public sewer or private leach field.You don't need venting if you size the pipe accordingly....I would use 3" in this case.Price isn't much more than 2" and you will never have a problem.....I would trap it before the exit with a "running trap" and put in a 2-way cleanout just to be safe. I wouldn't use the all-in-one units you describe and why do you need backwater valves? Just an unnecessary complication IMHO.Just use a 3" drain like this one.....http://www.siouxchief.com/products/...ous/bell-trap-drain/bell-trap-drain-cast-iron They are $21.21 with free shipping at Jet.com

 

[mike_dmt]

Hi,
Just pouring slab and setting up two floor drains. They are all-in one units with traps and back water valve built into drains. They will run to just outside my slab and dump into a below grade pit or french drain. Do I also need to run a vent line for trap venting?

I think some guys aren't reading the question quite right.

If I understand what you are saying, you are putting in the drains that have a TRAP built into them. Then yes, you would want to vent it the same as any other plumbing fixture.

You will need to take that into consideration during layout, because if you put the drains too far from a wall to run the vent up into, you will run out of grade for the vent line, and you definitely don't want a pipe just under the finish grade of the slab.

If it was me, I'd forego that drain style altogether, and skip the trap and vent, since you're not connecting to a sewer system of any kind.

And, I'd plumb it in 3" pipe.

 

[dirttracker18]

Hi,
Just pouring slab and setting up two floor drains. They are all-in one units with traps and back water valve built into drains. They will run to just outside my slab and dump into a below grade pit or french drain. Do I also need to run a vent line for trap venting?

Two things
First I ran the same idea, a floor drain to a dry well and have no trap and no issues with smell.
Second, why are you wasting money on a back flow setup that should not even have the ability to back up?