How can I make an exposed water supply pipe usable in winter?

Question

Our summer cabin in central Ontario has water supplied from a well. The line is well buried except where it enters the cabin - the cabin is on blocks above ground level and the line is exposed for the 2 or 3 feet under the cabin.

Currently it's protected using a "remote valve" - the cutoff on the supply line is a valve well below ground level with a long rod that runs up into the cabin where you can open it to drain back to the well during the winter. There's also one of those electric heater cords on the exposed section of the line, but we've never used it and I don't even know if it works.

What do I need to do to make use of that connection? I assume you simply can't pile dirt around it because it will eventually freeze, and I don't trust the heater cord (power goes out all the time). What's the typical solution here?

Answer 1

I suggest you build a well insulated box around the pipe from the ground to the floor of the cabin, then open the box to the cabin interior by replacing the floor over the box with a grille.

The box should be made of masonry or other rot-resistant material. The bottom of the box should be set about a foot or so below ground level for a better seal. I'm picturing a box that is about as wide as it is high.

The top of the box should not be strongly attached to the cabin floor because seasonal freezing and thawing may cause the box to move slightly. Instead, the top of the box should be sealed to the cabin floor with flexible insulating material. For example, a flexible gasket can be made with chicken wire, polyethylene sheet, and fiberglass batting.

Now, cold air is heavier than warm, so you have to keep the box from just filling up with freezing air. How you do this will depend on how the cabin is heated, how airtight the cabin usually is, whether the cabin is kept above freezing at night, etc.

If you can construct a chimney-like structure inside the cabin that is either warmer than the room (because it is near the stove) or colder than the room (because it is against an outside wall) and connect its bottom to the pipe box, that should provide sufficient draft to displace the frigid air.

Of course this solution depends on the cabin being heated in winter. If the cabin is allowed to freeze then you already have the best plan in place with that remote valve.

Answer 2

Your entire concept is bankrupt because you can't reliably heat the cabin. No matter what you do, when the cabin power/heat fails, the pipes will freeze.

The problem is, the water pipe can freeze anywhere from where it first rises above the frost line underground, to anywhere in the cabin.

Your frequent power failures are a deal-killer here. A diesel/propane autostart generator for a totlly unattended cabin is just crazy! So you will either need to come up with a Tesla PowerWall type scheme, possibly augmented with solar panels; but that will not work if your heat is electric or heat pump*. Or else some sort of electricity-free furnace system running off the propane tank, like the Empire style floor and wall furnaces widely used throughtout California and Florida. So I would go with one of those, if you didn't mind being the only one in Ontario. For some reason, despite the desperate need due to frequent power failures, no HVAC dealer in the snowbelt has ever heard of an Empire furnace.

• Note that if you are currently all electric*, and add an Empire, you will need propane service

To keep the pipe above the frost line from freezing, I would sister it with 2 or 4 larger pipes, wrap those with 6" of foam insulation, and circulate antifreeze through the 2 other pipes up to a heat exchanger inside the heated cabin. This will not require much circulation; a tiny pump of a watt or two will do; and this could be on a battery with makeup power coming from hydro, a small vertical solar panel, or both at once.

* readers, electric heat is common in Ontario due to a glut of hydro and nuke, in fact "hydro" is slang for the power company. Their other plants are shamefully coal-dirty, but the hydro/nuke has such a large chunk of the pie that they are probably the most renewable province/state on the whole continent. Assuming you count thorium as "renewable", and their wackadoodle CANDU reactors lend themselves to thorium.

Answer 3

You may want to consider plumbing in a special piping valve called a water hydrant. These are designed to have a handle at the top to toggle up that then lifts a rod inside the pipe to open a valve at the far (deep) end of the pipe. When the hydrant handle is toggled down the valve is closed and there is a side port at the far end that allows the standpipe to drain.

A properly installed water hydrant has a drainage field installed at the bottom so that the standpipe can drain away into the adjacent ground. This is often provided by installing course gravel or crushed rock in the bottom of the hole. Of course these need to be installed so that the deep end is well below the freeze depth.

This type of unit is very commonly used on farms and ranches where water is piped out to remote locations underground and then brought to the surface for the purpose of filling stock tanks.