Designing a cabin water system for easy winterizing..

[Ernest T. Bass]

Hey guys!

We're helping some friends convert their garage into a cabin/guesthouse. They will be living in the garage until their new home is built... The garage and new house will share the same well. Is there some way to install the water piping in the garage so that it can be drained easily? The problem is, the well will always be on for the main house, but the garage will most likely need to be shut off at times during the winter. Seems a shutoff valve below the frost line just outside the garage is the only way to give yourself a low point to drain the pipes from, but you'd have to make an insulated mini root cellar or something to have access to it. Is there an easier way to do this?

Oh, as long as were on the topic of plumbing a garage.. We will be building an insulated wood floor over the slab, and there will be a raised section under the bathroom that most of the pipes will be run through. We're contemplating what medium to use for the water piping.. I think PEX would be a safer way to go, since the pipes won't be easily accessible under the bathroom and the garage will be heated with wood, so an accidental freeze is a possibility... Thoughts?

Thanks!
-Andrew

[MountainDon]

Not sure what the best thing is for a shutoff deep enough down to not freeze.   

A gate valve could be installed below frost level easily, but draining the pipe from that valve up into the garage space is the problem. 

As for what piping, PEX is so easy as far as I'm concerned there's little reason to use anything else. You do need a special tool though. pexsupply.com has lots of the fittings, tools, etc. My Lowe's also sells PEX and one of the HD's near me sells PEX as well.

I have a normally capped tee in the cabin plumbing right at the main supply. I can hook an air compressor to it easily (I use one of the Ryobi 18 volt PlusOne) and blow the pipes out when required.

[lobster]

i have a pressure activated drain valve in the well - if pressure is above say 2 psi, it does nothing, but below 2 psi it opens and allows all water in the supply line to the house to drain out of that line and into the well (the supply line continuously slants upward as it goes to the house.)

so for me simply turning off the pump and then opening a faucet in the house eventually drains the underground part of the system. of course i have only one destination for the water - the house - and not two as in this case.

but i don't see why it wouldn't work with two. you would install an underground shutoff valve as you already surmised, but now you install two of them: one for the house & one for the garage. then temporarily close the house shutoff valve, turn off the pump, and open a faucet in the garage. the garage supply pipe will drain. then close the garage shutoff valve, open the house shutoff valve, and turn on the pump. the only inconvenience will be loss of water in the house for  few minutes.

[Ernest T. Bass]

That sounds pretty slick... Is there any possible way to have an underground shutoff that can be controlled from the surface? Kind of like a frost-proof yard hydrant?

[MountainDon]

That sounds pretty slick... Is there any possible way to have an underground shutoff that can be controlled from the surface? A pipe with a rod through it that you can turn or something?

I have a couple valves underground here at home. I got them at a big box store in the irrigation section (lawn sprinklers, etc.) There is a steel rod with a fork end that engages the metal handle on the valve. I welded an old socket to the rod and use a speed wrench handle to open and close. There's a 4 inch ABS pipe that extends from the surface down to the valve.


http://www.amazon.com/dp/B00004S22U/ref=asc_df_B00004S22U956826?smid=ATVPDKIKX0DER&tag=dealt7363-20&linkCode=asn&creative=380341&creativeASIN=B00004S22U

http://www.amazon.com/Orbit-Sprinkler-System-Underground-41045/dp/B0002YUB6M/ref=sr_1_30?ie=UTF8&s=hi&qid=1257825028&sr=1-30

links are for visual references, not a recmmendation as to where to buy...

[Ernest T. Bass]

Sounds like that would work well in our situation.. Think you'd want to put some type of insulation in the sleeve pipe? Or maybe just a large foam lid that covers the whole setup?

EDIT:

Instead of a pressure activated valve that drains back into the well, what about a simple sprinkler drain valve installed in some gravel below the frost line on the cabin side of the shutoff valve?

http://www.amazon.com/CHAMPION-IRRIGATION-DV-050-Valve-Drain/dp/B000H9MRBY/ref=sr_1_22?ie=UTF8&s=hi&qid=1257826150&sr=8-22

If that would work, you could drain the cabin without messing with the house.

[MountainDon]

My experiences with those type of drain down valves has been mixed. In our lawn irrigation system (which is no longer in service) I had grass roots growing into the valve causing leaks. Maybe that was because in that use there is drain down and water exiting every time the sprinkler shuts off. If under constant pressure perhaps they would hold a seal and prevent root intrusion.   



I never uses any insulation, just placed the valve at 36". Our worst frost depth is supposedly 18" but I don't think we've ever seen that. I suppose an insulation plug would keep the cold drats out. I used a screw in clean out plug just above ground level, hidden behind a bush.

[Ernest T. Bass]

Guess I'll have to do a little research on the dependability of those things.. Sure sounds like an ideal system though. Thanks for the help!