Pole Barn concrete floor for bathroom

[twosocks90]

We are finally putting a concrete floor in the pole barn and I want to put a bathroom out there. Now is the time to set the sewer and supply pipes, before the concrete is down. The problem is that I'm getting conflicting advice on whether the bathroom slab needs to have footings under it.

Bathroom will be approx 5' x 7'. The building is unheated except for the bathroom which will have a baseboard heater to keep the pipes from freezing. I'm also installing a stop box and a way to drain the lines in case I don't want to keep it heated.

So, the question is can I just put the slab on gravel like the rest of the floor or do I need to set footings below the frost line 42" down and then set the slab on that?

 

[ConCretin]

I suppose you could create a frost protected bathroom structure within the larger building but it seems like a lot of work and raises a whole new set of questions.

I think I'd opt for a simpler approach. Presumably your water lines will be below the frost line so i'd sleeve the slab and configure the piping to allow for some movement. The sanitary lines are probably more shallow and would just move with the slab. Just as important would be a good frost resistant base to minimize movement in the first place.

 

[HoosierMark]

The issue is the potential freezing of the supply line. Frost will go down 42 " in your area but it also goes sideways that far without a barrier. If you dig the lines down deep enough I would not think you would need footers.
My brother has a pole barn out near Omaha and he put a bath and small room for a fridge in it. He put lines in the floor (enclosed area only) and uses a hot water heater and small circulating pump to keep the space warm. It has been several years now and he loves it.

 

[finn]

Never heard of doing anything special like a footing for a bathroom around here.

Put vertical foam at the slab edge, at least by the bathroom, and keep the room above freezing. Make sure you can blow out the pipes. Use pex, and rv antifreeze in the traps if you aren’t heating it for a period of time.

 

[twosocks90]

I originally wasn't going to put the bathroom out there by my son persuaded me that since the water line is right next to the building, it would be great to have the bathroom. The more I think about it, the more I agree with him. It would be great to have a place to wash hands and such without going inside the house.

We're going to sleeve the supply line and just bed the sewer line in sand or gravel. I never thought of frost travelling sideways but that makes sense. Thanks for the suggestions. I am really looking forward to this now.

 

[NUTTSGT]

I use a frost free hydrant on the water supply for my garage. If need be, I can shut down the water.