Adding interior main water shutoff

Old 09-16-22, 09:31 PM
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Adding interior main water shutoff

I want to add an interior shut off valve in my garage. I'll be doing some "remodeling" this winter and will have the ability to open the wall on the side where the main water line comes in. My big question is can I use PEX or would it be better to use copper?
Old 09-17-22, 12:51 AM
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Copper is basically forever, PEX is just a cheap alternative, nothing I would ever have in my house but that is just my preference!
Old 09-17-22, 04:37 AM
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In my area it is the exact opposite. The water chemistry in our county corrodes away copper so PEX is the preferred long term option.

Yes, PEX is approved everywhere in North America as far as I'm aware. Since you mentioned a garage if you are in an area with freezing weather PEX is much better if the pipes ever freeze. Copper will often split when the water freezes but PEX tubing stretches and is not damaged.

Unfortunately PEX has no structural strength like copper. So, with copper you can let the pipe hold the valve. With PEX you can do the same but it will be a bit "floppy" so I like to mount the valve so it has a nice, solid feel.
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Old 09-17-22, 05:01 AM
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I would suggest sticking with whatever material is currently there. IMO, adding a 12" piece of another pipe material can look unprofessional as opposed to just sticking with what's currently there. But, there's really no code issue with any approved method.

But since it's your water main coming in, I would be sure to add a wire jumper around the PEX if you go that direction, and if the rest of the system is copper.
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Old 09-17-22, 05:59 AM
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Good point about the jumper wire. I guess that is why using water piping is no longer code for electrical grounding.
Old 09-17-22, 07:14 AM
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Thanks for the info. As far as weather, I'm in Texas so no real freeze threats. Not worried about the looks since I plan on putting it behind a panel so it won't be exposed. Looks like I have a little project ahead of me.

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