PEX and floor drain

[wedge40]

Have a (new) barn that I plan on putting concrete down.
I will have 5" of concrete with 1/2" rebar spaced 18" and 1/2" or 3/4" pex ran along the rebar for heating the area.. Should I try and put a floor drain in or just let any water evaporate. Seems like adding a drain while running the pex would add to the complexity of the thing.

Wedge

 

[joeyd]

If possible I would always vote for a floor drain. My concrete pole barn floor does not slope well enough to channel snow melt to the outside. (I asked the sub to make it slope). Plus the apron I had poured at the same time was not tied into the slab so in the winter it heaves and makes a lip that prevents even squeeged water to flow out the door.

 

[verstore]

I would think that your floor drain lines carrying water to the outside should be placed well below the rebar and Pex for radiant heating. Place forms for the sump (or whatever collector structure you want) and place the rebar and Pex around it. There are countless ways of covering a sump, etc. to allow water to flow in and provide access for removing the crud that will collect over time. Be sure to place the outlet from the sump into the drain lines, above the bottom of the sump to allow for settling of solids. Immediately after liquids leave the sump I think you should include an inline trap, regardless of the eventual destination of the water collected.

 

[YogiBear79]

I recently built a 40x40 building with pex heat and 3 floor drains. The drain boxes were the only thing to work around, the pipes were below the 2" insualtion. SO running the pex around the boxes was no big deal

 

[jimgerken]

What are the options for the floor drain boxes? I am doing the same thing as the OP, and have not found a good off-the-shelf drain box option. I want sand trap, and liquid trap so air does not flow into the building through it. Pictures? Links? THanks!!!

 

[5030]

In this state, floor drains in outbuildings are a big no. However, I have Oxygen Barrier PEX heating in my new shop addition and water on the floor isn't a problem, it evaporates quickly when the system is on, in colder months.

My slab is thicker than most because it has to carry machinery. I'm 8" thick, 4 bag mix with 3" of expanded foam below that on a tamped sand base. I used prefabricated galvanized cattle panels in lieu of rebar and stood the PEX off the panels with factory made standoff's.

Last winter I heated the building and the existing (forced air) shop with a 30 gallon water heater set on warm. I have 3 zones, 2 in the mud and 1 running through a stand alone HX with a fan behind it (in the older, existing shop). I kept both areas at 70 no matter what the outside temperature was.

I run straight Cryo-Tek (glycol) with Califfi manifolds, a Taco pump and assorted hardware. I used a remote sensing Honeywell Commercial T'stat with the probe in a thermowell in the slab itself. That way, the t'stat senses the slab temperature and not ambient air.

My total bill on propane for the entire year was about 700 bucks.

 

[wedge40]

I've been looking around and have decided to skip the drain. Like 5030 said, in the winter I'm pretty sure the water will evaporate quick with the heated floor.
Besides I'm not sure what my local gray water requirements are.

Wedge

 

[5030]

I've been looking around and have decided to skip the drain. Like 5030 said, in the winter I'm pretty sure the water will evaporate quick with the heated floor.
Besides I'm not sure what my local gray water requirements are.

Wedge

Midwinter, you'll actually want some water on the floor to turn to vapor to relieve the low humidity. It gets drier than a ragweed fart in my shop in midwinter with the Pex floor.

However, it's the best heat I've ever experienced. Warm feet on a cold day can't be beat and it's a steady heat unlike conventional forced air or radiant baseboard. The mass is warm and radiated heat in a very uniform way.

My wife's barn cats congregate in the overhead door well at the front of the building. The slab extends there, to the apron and it's always warm and dry despite how much snow we get.

 

[Chilly807]

I've been looking around and have decided to skip the drain. Like 5030 said, in the winter I'm pretty sure the water will evaporate quick with the heated floor.
Besides I'm not sure what my local gray water requirements are.

Wedge

I wish I had put floor drains in my garage floor, which is heated with pex pipe. It's too late now, you can't even cut drains after the pour unless you know exactly where the pex pipe is.

If you're in doubt as to local laws, it's worth checking anyway. If it's only to catch snow melt, etc, I'd suggest setting the drain top plate 1/4" below the floor surface and cover with poly plastic when the floor is poured. After the inspection is finished, break out the thin film of concrete and your drain is usable.

My barn drains simply go into the rock under the floor, all they are for is to catch snow melt in the winter.

If the snow is going to melt anyway, what's the difference where it does it??

If you do decide to go with drains, be sure to slope the floor accordingly, or else you're wasting your time.

Sean

 

[Kays Supply]

It can't cost much to put at least one drain in, even if you don't connect it outside. It will always be there if do decide you need it. It won't take but a few bucks to put a toilet rough in also. Like it has been said , you can't go back. You can always plumb a sink into the vent from the stool if that is all you want some day.