Is it OK to run the main water supply line up into attic to be supplied throughout the home?
Cedric Stephens| Posted inGeneral Questionson
30 year or more home, built on a slab, and water lines are being damaged and lines are breaking. All lines are coming from under the slab in each part of the home where water is needed.
I now have a water leak that could be further under the slab and not reachable. I recently repaired a pipe at the back wall of my home where as l had to dig under the slab and it was reachable. Now at this time this leak is not and cannot be seen. What must I do?
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Replies
Do you live where it freezes in winter?
It's hard to repair under-slab plumbing when it starts to fail in multiple places. I would re-route it into the attic and down to each fixture. Best case IMO is to use continuous runs of PEX with NO fittings in the attic, so your plumber will have to plan the layout a bit, and the pipe should be very well insulated and protected from damage so that people walking through the attic insulation can't step on it.
Cedric,
Sorry to hear about what must be a very stressful problem. David has given you good advice. Make sure the new water lines are run close to the ceiling and that there is adequate insulation above them.
Cedric,
It would still be useful to know your location or climate zone. In very cold climates (northern Minnesota or northern New England, for example), it's hard to keep water pipes from freezing if the pipes are located in an attic.
In cold climates, even a very minor air leak or air pathway that allows exterior air into the attic and through the insulation can freeze plumbing. The problem is solvable, but any contractors who work in the attic must understand the issues and pay meticulous attention to air sealing and insulation.
I live in southeast Texas, not much winter.
Cedric,
In your climate, plumbing pipes can be installed in an attic, as long as the pipes are installed under the insulation layer. (It wouldn't hurt to insulate the pipes with foam pipe insulation before the pipes are buried.)
Needless to say, if you find the work daunting, you should call a plumber.
It's the standard fix for pinhole leaks in under-slab copper
in Florida. My parents had to do it to their place, and quite
a few other houses in the area suffer the same problem. Of
course the runs are all uninsulated, so daytimes bring a nice
big slug of rather hot water out either tap.
While I would have expected components from the concrete to be
responsible for the corrosion, apparently it's the water itself
because the pinholes evidently start on the *inside*. Full of
sulfides and other yuck; water quality isn't very good there...
_H*
Hobbit,
Another good reason to sleeve your waterlines under slabs. Pex in 3" PVC with sweep elbows can be replaced whenever the whim strikes.