[QUOTE=ZipperJJ]
What are the downsides of PEX?
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[QUOTE=friedo]
PEX requires specialized tools. You also don’t want to leave it exposed to sunlight. Other than that I can’t think of any big downsides to it.
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If you’re just starting out, all piping materials need specialized tools, but a plumber with more than a month’s experience will already have copper tubing cutters, reamers, soldering torch, PVC pipe cutters, PVC primer and cement, etc… The original style fittings for PEX do require special expansion tools, but there are newer “sharkbite” fittings that are DIY-friendly, requiring only a smooth square-cut end on the tubing, which is simply pushed into the fitting. They’re rather expensive, making them unlikely to be used by a professional plumber.
The sunlight issue is a big one for PEX - two to four weeks’ exposure to sun is said to completely deplete PEX’s resistance to chlorine, which can lead to a severely shortened lifespan before bursting.
Another problem is it can’t be recycled. Nearly 100% of copper pipe gets recycled, but so far, about all anyone’s figured out to do with old PEX is to pulverize it. So then what do you do with a pile of plastic sand? PEX is a thermoset plastic, so it can’t be chipped up and re-melted like vinyl or PVC.
[QUOTE=snowthx]
Are the waste water pipes also copper? Thx
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I’ve never seen copper drain lines in a house, but the materials do exist. AFAIK, San Francisco may still require copper drains in commercial buildings. It’s breathtakingly expensive.