Emergency Floor Drain In Basement

[dosby]

As part of my walk-in basement renovation, I am redesigning a washer/dryer closet into a wetbar/laundry area. I am adding a kitchen/utility sink, overhead cabinets, etc.
I have bare concrete floor throughout my whole basement now.
In the laundry area, I am thinking of installing an emergency floor drain in case my new washing machine behaves. That is actually the only reason since the basement has remained dry all the time.
I am thinking of drilling a 2-1/2" hole through the concrete foundation wall right to my backyard, which slopes away nicely so that water would drain there fine. I understand I need to install at least 2" PVC pipe.
What I could not find online, is what kind of floor drain fixture to use and how to best install it.
Bust the concrete floor? How deep?
I understand that for emergency drain a p-trap is not needed, correct?
My washing machine would sit right above the floor drain on adjustable legs. I am not planning to install any flooring in the laundry area.
Is that a good plan?
Attaching a planning pic: grey squares are washer/dryer, the ext wall is on the left and the backyard starts sloping down ~6' from the wall. Interior concrete floor is level with the gravel outside, I think I could dig it up and lay a pipe there. Ext wall is ~8" thick with concrete up to 12" above the floor, not sure how deep in the ground it is.
Thanks!

 

[Terry]

Normally a concrete slab is at least 4" thick. I have also seen 8" but that was just odd.
Drain pans under washers are ported outside with no problems. They normally do that with a 1" drain.

 

[Sponsor]

 

[dosby]

Normally a concrete slab is at least 4" thick. I have also seen 8" but that was just odd.
Drain pans under washers are ported outside with no problems. They normally do that with a 1" drain.

Thanks!
The concrete is 4" thick - I relocated drain recently (bathtub -> shower conversion) and had to bust that same concrete floor.
I am also thinking of not using a pan so that the same floor drain would help in case the whole basement floods.
So should I use just a bulkhead drain, then?

 

[dosby]

So if I do have slab-on-grade (which I think most likely the case), is it better to go under the slab or drill through it?
Where do they usually place re-bars? Deep below floor level?

 

[dosby]

Bought a 13" long 1.5" dia core drill bit for concrete with arbor, should be fine for 1" pipe, I guess. And I already have a hammer drill. Should be a fun project. I am planning to drill a pilot hole first all the way to the excavated outside trench.
Are there any good floor drain fittings for 1" pipes?

 

[Cacher_Chick]

We are not allowed to place any piping smaller than 2" under concrete. This allows it to be rodded in the future.

Something like a water heater or washer pan is normally installed near an outside wall, in which case we run a short stub of CPVC across the floor and out through the side wall. If the heater were not on an outside wall, we would have to install a proper 2" floor drain.

 

[dosby]

We are not allowed to place any piping smaller than 2" under concrete. This allows it to be rodded in the future.

Something like a water heater or washer pan is normally installed near an outside wall, in which case we run a short stub of CPVC across the floor and out through the side wall. If the heater were not on an outside wall, we would have to install a proper 2" floor drain.

Well, my good neighbor Terry suggested 1" PVC pipe, and, yes, my washing machine is right by the outside wall. I was also thinking 2" first, but that might be an overkill for overflow drain.

 

[Cacher_Chick]

Well, my good neighbor Terry suggested 1" PVC pipe, and, yes, my washing machine is right by the outside wall. I was also thinking 2" first, but that might be an overkill for overflow drain.

Right 1" through the wall is fine, but not under the floor.

 

[WJcandee]

Where do they usually place re-bars?

I would have thought you would have run into it if you have already busted up the slab for your other project. One caution: I don't think that post-tensioned tendons are or were popular in Washington State, but I would want to be sure that you don't have one if you are drilling or cutting into concrete, particularly if you aren't seeing rebar in the areas you already busted up. Cutting a PTT is gonna release about 33,000 pounds of load, which can damage you or the slab. Usually, the tendon runs through the center of the slab on 48" centers for residential applications. Often, there is some residual marking that will let you know that you have a post-tensioned slab.

Anyway, this is probably an unnecessary warning, but it's always something to keep in the back of your head when cutting into a slab that you didn't order yourself. California and Texas account for somewhere under half of all residential post-tensioned homes. Louisiana has quite a few in areas where the soil moves, and I seem to recall Nevada and Arizona having their share... Just not sure about Washington.

 

[dosby]

I would have thought you would have run into it if you have already busted up the slab for your other project. One caution: I don't think that post-tensioned tendons are or were popular in Washington State, but I would want to be sure that you don't have one if you are drilling or cutting into concrete, particularly if you aren't seeing rebar in the areas you already busted up. Cutting a PTT is gonna release about 33,000 pounds of load, which can damage you or the slab. Usually, the tendon runs through the center of the slab on 48" centers for residential applications. Often, there is some residual marking that will let you know that you have a post-tensioned slab.

Anyway, this is probably an unnecessary warning, but it's always something to keep in the back of your head when cutting into a slab that you didn't order yourself. California and Texas account for somewhere under half of all residential post-tensioned homes. Louisiana has quite a few in areas where the soil moves, and I seem to recall Nevada and Arizona having their share... Just not sure about Washington.

I did indeed cut into rebars when I was moving my drain in my 4" slab. I drilled holes and inserted new ones when patching the trench, not sure if that helps at all, mostly to keep the trench from sinking, I thought at that time.
Footings could be a different thing, I get it. My plan is that if I encounter a rebar when drilling under floor level, to move the hole sideways 3-4" and down-up 1-2" (depending where exactly the rebar is) and start all over again. I heard that advice to avoid cutting the rebar, but it may be helpful with house's stability, as well, not to cut it. My hope is, thought, that rebars are not the only thing holding the foundation together. Unless I cut all of them.

 

[dosby]

Right 1" through the wall is fine, but not under the floor.

I see, so what you saying is that the pan should be filling up to the drain level first, and then the water would drain outside. I was thinking of avoiding a pan altogether by placing the drain in the floor, and maybe even sloping the floor towards it just a tiny bit. I could always balance the washer on it's legs for that tiny slope.

 

[dosby]

Finally got it done (too many projects at the same time)
I dug out a mini-trench just outside the foundation (gravel then cloth then soil) and found an open end of a storm water 4" corrugated pipe, going right into the ground at an angle. Checked with a garden hose - drains perfectly fine. Decided to route my emergency drain right there instead of digging up another 10' of trench into the lower level of my backyard.
Coincidentally, there was a small metal plank (and some wood remnants) going right through the foundation wall ~3-4" below the concrete floor level. That was exactly where I was planning to drill the hole for my 1" CPVC pipe. No rebars there, I drilled around that plank at the slightest angle and pulled it out. I think it used to hold two sides of a concrete form structure together. Can't think of any other use for it.
Busted the concrete floor on the inside, put a simple 3" drain cover there over a 3" PVC coupling which had one end of my 1" drainage pipe inside with a 90 elbow turning up. I covered that opening with a wire mesh and later cemented it all together. Basically, the water would flow into the 3" PVC coupling, then into the 1" pipe end and out to the outside drainage pipe. I wrapped that corrugated pipe end in a 4" sleeve and covered with soil. I will cover it again with a garden cloth and then gravel and call it done. The outside end of a 1" PVC is draining into the pipe through a hole I cut in the corrugated pipe and then downwards at 90 degree elbow.
And yes, I used regular blue PVC cement to attach elbows to the CPVC pipe. No cementing between corrugate pipe and 1" pipe, obviously, just a loose joint of one into another.
I will take/post pics tomorrow, now it's too dark.