Installing water line to hose bib under floor

Old 11-06-17, 06:12 AM
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Installing water line to hose bib under floor

I need to install a new hose bib in an addition I just had built, and need to know if it's okay to run a 1/2" copper pipe under the floor between an insulated slab and wood subfloor (floor system is 2x4 sleepers on top of a concrete slab). Code says it's okay if it is a "semi-conditioned" space. The floor cavity will be open to the ceiling of a finished/conditioned basement, so I'm hoping this will suffice. I also need to install an air duct under the floor to feed a new register, so perhaps I could run the pipe in the same cavity.
Old 11-06-17, 12:50 PM
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I would never do anything in copper. I would run the new water line in PEX. If it ever does freeze it will not hurt the pipe.
Old 11-06-17, 01:18 PM
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Especially if the line has to penetrate the concrete, I would also avoid copper and go with Pex.
Old 11-07-17, 09:28 AM
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No problem. It sounds like your 'crawlspace' (even if it's not really crawlable) is insulated, so will be closer to the temperature of the house than the temperature outside.

I would try to run it somewhere into the living space and add a shutoff valve with drain there. That way if you do end up with some exceptionally cold temperatures, you can shut off the water and open the outside hose bib to drain much of the water out.

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