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matt46b
Underground water line help
matt46b

I need to run some pex from my basement to an unattached garage about 20ft away. Geeting it to the frost line and to the garage I don't need help on.

What I need to know is that when I get to the garage, I'd like to keep it as painless as possible.

First question is what you do to protect from freezing as you rise up above the frost line ?? Just insulate really well?

And secondly -- I guess the ideal way is to go under or through the footings (that would be a *&^) and up through the slab?

But I'm hoping that somehow I can come up the side of the footings and into the cinder block and then into the wall of the garage, ? Life would be so much easier but again what do you do to protect the pex from freezing?

thanks very much -- looking to hear definitive answers -- please don't "guess".

Mastercarpentry
Re: Underground water line help
Mastercarpentry

Were this me, I'd drill just inside the cinderblock diagonally through the slab toward the perimeter. Feed the PEX in from this point going as straight down outside as you can to the needed depth. I'd insulate between slab and bottom with slip-on foam. Do the insulation on the other end similarly. Don't insulate between- you want the soil warmth there to help keep the rest warm where it turns up. Insulate the pipe inside the structure the same way if needed. You may hit rebar when drilling, adjust the angle to clear it if you do.

You can rent a hammer drill and bit for half a day for about $50 here and it's worth it. One place has better hourly rates. Make that hole oversized and fill the space with a can of expanding foam once the PEX is run. A bit of work involved but easy on the DIY scale. Done this way you should never have any problems and if you do, the PEX can be pulled and replaced easily.

Phil

matt46b
Re: Underground water line help
matt46b

Phil -- thanks a lot. That's what I was hoping someone would say. I guess I should take that angle as far down as possible but I'm an old fart may have to get a kid doing the jack hammer. Do I dare taking it straight through the bottom of the cinder block and maybe even extend the interior wall a bit to cover it with room heat? Like a shroud or something? Think that might work ? plus of course the insulation and foam. thanks again

ed21
Re: Underground water line help
ed21

If I could comment, I don't believe Phil meant a jack hammer, but a hammer drill. Not that hard to handle, although getting a kid to do digging and drilling is never a bad idea.
His angle method will allow you to drill a straight hole from the foundation wall through the slab. Drilling straight in will require part of the slab to be removed in order to creat a hand hole in order turn up the pipe. Which by the way wouldn't be a bad idea if you wanted to install a frost proof hydrant type of fixture if the shop isn't heated.
Part of your original question- pipes generally should not go under a footing. In new construction the footing would be dropped as required where pipes pass through.

Jack
Re: Underground water line help
Jack

If you only need the water in the garage during warm weather you could put a line drain in the house to drain the line in winter and not worry about.

Jack

matt46b
Re: Underground water line help
matt46b

yes -- I knew he meant hammer drill -- Ok thanks you guys. Again though what if I do something that actually takes the room heat around the incoming pex someway?

maybe like an outside box (6 to 8" square?) that completely surrounds the pex and go down into the soil as deep as I can get it? seal it to the house with zero air leaks and have a substantial opening (say 4" wide by 8" high) that actually sees room air and all the way down the box, which I'd insulate really well. This is going to feed into a utility room, so I wouldn't care about having the open "port" in the wall. the opening would be in the wall just above the cinder block. and with no air leaks so I don't think I would lose heat from inside much ?

may just be easier to do the hammer. as I say old fart with arthritis and anymore I try to keep my joints from banging.
but I'm no couch potato-- love the work.

Mastercarpentry
Re: Underground water line help
Mastercarpentry

By drilling as I suggested the slab ang lower groud helps heat the pipe, it's not exposed, and short of adding auxiliary heat will be as frost-proof as is possible. Drill the slab just inside the block wall at a 30-40% angle from vertical then catch the pipe from under the slab. The big hammer drill you'll need might be rough on arthritis but it's not too bad for most folks.

Doing this any other way that will be equally or more reliable won't be cheaper, faster, or easier to doe. Trust me, with our diverse experience here at least one of us has already tried every feasible alternative you can imagine and then some. We had to repair those mistakes ourselves and we're simply trying to save you that grief. Do it any you wish, but when that fails don't expect a different answer when you want to know how to fix things afterwards, because you'll get the answer we already gave.

Do it once, do it right, and be done with it. Any other way is wasted time and money.
Phil

keith3267
Re: Underground water line help
keith3267

If the garage is unheated, the pex pipe will freeze no matter how you run it. If you have power, you could use a heater cable for the pipe.

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