We have a slab leak most likely caused by the underground hot water soft copper pipe. The cost of repairing it in the slab is about $1000 but due to the age of the house (26+ years) and many neighbors having similar slab leaks, we are leaning towards doing the both hot & cold water reroute (costing about $5500 - $7000).

The two plumbers (who have given me the rough estimates) have different opinion on the type of copper. Both will use type L but one would use the hard one & other perfers the soft.

First plumber doesn't seem to have any specific issues w/ the soft one but says it is not necessary & doesn't look professional (even though its inside the wall). Also, he thought you can't really bend it enough to avoid the joints as it has to be run thru the walls.

2nd Plumbers suggests that soft copper is easier to use for re-running thru the house and requires less joints and thus lessens the chances of future joint failures.

I haven't found any clear guidance on the net about either of the two types (soft one mostly for underground type & hard for inside the house), so I thought of asking the pros here:

1. For indoor reroute in SoCal, are there any clear advantages of soft vs hard copper pipes?
2. Does soft copper has same strength as hard?
3. Is soft copper susceptible to kinks and can those happen while re-running it?

We will appreciate any guidance you can provide!
Best,
SanSoo

and just what is wrong with pex ??

I am old school and not a PEX guy. You asked the following:

1. For indoor reroute in SoCal, are there any clear advantages of soft vs hard copper pipes?

Like one plumber stated you can limit the cutting of drywall to some extent using soft, but it is more expensive and like he said does not look as neat as hard copper. Definitely use type L don't use M.

2. Does soft copper has same strength as hard?

They are both rated for more than 150 psi so not an issue.

3. Is soft copper susceptible to kinks and can those happen while re-running it? Yes soft will kink but a pro will not bend it to kink it. Once kinked it is a weak spot in the tubing and can fail earlier than the rest of the system. Many under slab leaks are caused from straightening out soft to continue to use after it has been kinked.



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Don't even think about anything but PEX to re plumb

Neither plumbers have recommended Plex. May be they are old school?

Thanks very much for your valuable input.

So soft copper makes the installation little easier as the cuts inside the walls don't have to be in perfect straight line in order to run the pipe thru it?

Also, what causes the kinks? Just bending it too much while maneuvering it?

Both hit n cold lines will run next to each other, anything to keep in mind there? Ground them?

Thank you very much!



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kinks are caused by making the radius of a bend too sharp.
as for pex vs copper pricing. i would say the price difference is anywhere from 3 to 5 times as much.