I need to run a water line from my house to my barn. The line will run through my basement, exit the house, and run underground to the barn. It's a walk-out basement with a concrete slab floor, and the wall where the pipe will exit the house is a stud-wall that's entirely above grade. I'm in North Carolina where the temperature can occasionally get down to the single digits in the winter, so freezing is an issue for any portion that's exposed to the outside.

Is it okay to run the water line out through the wall, down the exterior of the house, and then into the ground? This saves me the enormous pain of drilling down through the slab and somehow tunneling under the footings to avoid exposure to the outside air. If so, what type of tubing should I use for the exposed portion and how should I insulate it?

Hi Jcaron2:

Only way to guarantee that the pipe won't freeze in the future is to bring the pipe underground as you suspected. If the pipe did freeze it could freeze into the home and burst a pipe inside... major bummer!

For best result you will want to find out the depth of the frost line in your area and you will want to run the water pipe below that frost line.

You will run either copper tubing, Type K or black PE pipe... no joints underground.

Sorry that the answer isn't easier, but this way you will not have to do the job twice... that would really be an "enormous pain"... ;)

MARK

Mark did a great job with this. Insulation just won't help one darn bit so if you aren't willing to drill out below the frost line then add some pipe heater tape that is thermostatically controlled. Since this is a barn can we safely assume you are on a well and where is that well head located? A well may be closer to the barn than running from the house.

I think this covers it very complete.

Installing underground water line to barn? - Plumbing Forum - GardenWeb

Instead of no copper, the link says brazed (i.e. Silver soldered) joints are acceptable.

For boring check out BulletMole®: The fastest, easiest, cost effective, way to install irrigation pipe or electrical conduit under sidewalks, driveways, and other hardscapes.

For drilling through the slab, you might rent a core drill (say 4 to 5"" hole) and sleave the slab portion.

You could drill with the bullet mole and then locate the mole with an electronic locator to figure out where to core drill.

So, it is doable - Just not an easy task.

Or you could use a good old-fashioned jack hammer and a shovel... works for me on all my jobs! :D I would run PE pipe... ;)
Great link Ron (KISS)!

Thanks, everyone. KISS, that was a great link. However, one thing has me scratching my head: The first follow-up post in that link specifically mentioned that the line to the barn has to originate on the discharge side of the pressure tank. Maybe I'm missing something, but I don't see any kind of check valve or back-flow preventer on the inlet side of my pressure tank, so why wouldn't it work to just connect at the well head? For that matter, my well guys installed a tee with an anti-siphon hose bib at the well head, and that works just fine, so clearly the pressure tank is supplying water back toward the well head. Would you agree that I can just install an additional tee at the well head, add a ball valve, and go from there to the barn?

Just so you know my thinking, I had originally decided against this approach for a number of reasons: The well is somewhat further from the barn than house. The line between the well head and the expansion tank in the house is 1" PE. I'd prefer 1.25 or 1.5" to get high flow rates in the barn, especially since it's 500+ feet from the well, so I was planning to hook the larger diameter line as close to the pressure tank as possible. And most of all, like the original poster in that link, I will have to deal with avoiding underground utilities if I connect there at the well head.

However, in light of the alternative of drilling or jack-hammering my basement slap, that option is starting to look a lot better now. :-)

So, all that being said, I have a couple more questions if you guys don't mind. 1) I can get PE pipe in 100' rolls, which means I'll need several unions underground. I've always seen PE connected with barb fittings with hose clamps. Is it okay to directly bury a hose clamp? Will it rust away at some point and potentially fail? 2) I can save a little bit of money if I run schedule 40 PVC (at the expense of a little extra work). The well head is covered with an insulated fake rock, and we've never had a problem with anything freezing in the past. Nevertheless, is the foot or two of above-grade PVC going to be as "tolerant" to a potential freeze as the PE? And finally, 3) Do you think my money would be better spent just running a smaller line out to the barn (e.g. 1") and putting an additional expansion tank out there?

Thanks again for the help and advice.
Josh

Here is some literatire on some pressure tanks:

http://www.watertanks.com/images/pdf...s-hydropro.pdf

I'm throwing it there because you had mentioned volume of water. The pressure tank creates pressure for the system in such a way that for small draws the pump doesn't have to come on.

Yes, the pressure tank will affect the entire system. There really should not be a definite in or out. Air is compressable and the standard tank is a bladder tank, thus adding water compresses the bladder and at the high shuf off the pump shuts off. You can draw down the tank and at the low pressure setpoint the pump turns on, so you can get a glass of water or flush the toilet without the pump running. So, that's the basic purpose.

FLOW which you apparently want to increase will be dependent on the minimum size of pipe in the system UNLESS the storage resovour has a larger pipe size. That increased flow will only last for the amount that can be drawn down and then it's limited by the size of the line feeding the tank and the pump flow rate.

If you really need the FLOW and VOLUME what you might be able to do is burry a pressure tank in the barn with the right capacity for what you might consider an good draw down level.

So, if you determine that you would like about 40 gal at a high flow, then get another pressure tank in the system, but just have one controller for the pump.

It is possible to complicate matters, by sensing the pressures at both ends and make the pump turn on if either pressures drop. I doubt that would be necessary because in a static case the pressures will be the same throughout the system.

What I'm trying to say in a simple fashion is that if there is a 3/4" restriction somewhere and after that 3/4" restricting the pipe pize goes to 10" diameter, you canonly have the flow of a 3/4" pipe.

Initial low can only come from the size of the outlet of the and the draw down, so you would be able to maintain a high flow rate (Limited by the pipe diameter) until the draw down was exhausted.

After that happens, your limited by the smallest pipe size and the pump flow rate.

By putting a buried pressure tank near the barn, you can get that higher flow limited by the outlet size of the pressure tank for whatever time is desired. So if you need 40 gal to fill water troughs, washing, etc. for a short time get a tank to cover that.

Increasing a 3/4" outlet of a pump to 1.5" doesn't do a thing except decrease the friction loss of the pipe.

Burrying the pressure tank reduces the possibility of freezing.

This is somethingto consider because of the distances involved. Branch at the pump and go in two directions or branch at the house and go to the barn.

Friction loss will result in a pressure drop and a flow rate drop.

This is just an alternate thought.

Determine the flows required and the amount of water on an intermittant and continuous basis at the barn first.

The pipe lengths are very long.

FWIW: Sprinkler lines are buried all the time.

Thanks, KISS. Very helpful as usual.

The other questions:

I think PE is more tolerant to freezing than PVC.

With distances that large, you should consider burrying locator wire. Color of the insulation differentiate utility.

PE can be welded and would be the preferred connection method. The diameter of the tube would not decrease as a result of the fitting.

The distannces suggest a tank at the pont of use.

Water requirements at the barn will influence the design choice.