Flutterby™! : Clearly

Next unread comment / Catchup all unread comments User Account Info | Logout | XML/Pilot/etc versions | Long version (with comments) | Weblog archives | Site Map | | Browse Topics


2012-03-11 23:46:07.913239+00 by Dan Lyke 16 comments

Clearly, it's time to re-plumb the house. Anyone got input on the copper vs PEX issue?

[ related topics: Real Estate ]

comments in descending chronological order (reverse):

#Comment Re: made: 2012-03-14 17:51:27.309955+00 by: m

As Larry mentioned, the quality and pH of your water supply is a consideration. Some water suppliers are required to maintain the Langlier coefficient within certain bounds. This prevents the build up of precipitates on the one hand and the dissolution of pipe material on the other. You can probably find out by calling your water provider, your local Health Department, or whoever is responsible for water quality in your area.

#Comment Re: made: 2012-03-12 19:08:36.61121+00 by: Dan Lyke

I'd have to check further for the details (including distances and such), but I beleive that in my jurisdiction non-metallic water systems must still have a metallic portion bonded to ground on both the cold and the hot sides within some short distance of the water heater.

This is independent of using the waterline pipe as a ground.

#Comment Re: made: 2012-03-12 18:39:31.760729+00 by: Larry Burton

According to code metallic water piping systems must be bonded to ground. (2008 NEC 250.52(A)(1)) This doesn't mean that they are to be used as the electrical system ground. It means they must be bonded to ground. This keeps the electrical system ground and the metallic water piping system at the same potential.

#Comment Re: made: 2012-03-12 18:17:53.693021+00 by: other_todd

I've been doing some looking since I made my earlier post, and I can't sort out the swamp of internet information on grounding the water pipes. Some sites think you MUST, some sites think you CAN'T (for new work) - but one general consensus seems to be that the increasing amount of non-conductive materials in water supply systems mean that a ground on the water pipes is no longer a sure bet.

#Comment Re: made: 2012-03-12 17:57:38.974464+00 by: Dan Lyke

Huh. Okay, I misinterpreted something somewhere. It appears that a single ground rod is indeed acceptable, and the #4 wire run to the water is just grounding the water system (further confusion, I do have an additional wire run from somewhere to the water pipe within 5' of where it enters the building).

So, yeah, I guess I don't really need to drive another rod or two. But now that I'm thinking about it I probably will.

#Comment Re: made: 2012-03-12 17:31:36.498403+00 by: other_todd

I am told - was told by the electrician who replaced our service panel, so I assume that he knew code - that (in Medford, MA at least) it is illegal to ground onto the plumbing, even if you've put a jumper over the water meter etc. I am surprised that it would be legal in your neck of the woods, the one place even more regulation-happy-for-your-own-good than Massachusetts. I would check on that - not that I'd necessarily let that stop me, but best to be informed of where you are in breach, eh?

#Comment Re: made: 2012-03-12 16:56:58.206187+00 by: Dan Lyke

When the electrician replaced the drop and panel shortly after we moved in, I didn't know a whole lot about electrical code. Apparently a single rod and plumbing is acceptable for retrofits. So, yes, I really should drive at least one more rod.

#Comment Re: made: 2012-03-12 15:56:06.541764+00 by: Larry Burton

Dan, you needed to beef up your house's electrical grounding system anyway if you were relying on the plumbing for grounding.

#Comment Re: made: 2012-03-12 15:50:05.319487+00 by: Dan Lyke

I think the preponderance of the evidence is leaning towards PEX. I don't think it will be any faster to install cheaper for my application (especially since this means I'll need to beef up the house's electrical ground system), but it seems like the right long-term solution.

I do need to do a bit of plotting about what fittings I'll need and how I'll set them up. Since we've got the recirculator, I'm thinking T'd ¾" at the building entrance, with half over to the hot water heater and washing machine, and the other half to the wall between the bathroom and kitchen. ¾" back from the hot water to that wall, with a distribution manifold to ½" tubing under either the bathroom or kitchen sink. That way the recirculator will prime to the manifold.

And because it's so cheap, I'll run a dedicated return for the recirc.

#Comment Re: made: 2012-03-12 15:41:07.686007+00 by: TheSHAD0W

There are new push-to-connect fittings for copper pipe, makes things a lot easier to work with. On the other hand, PEX is good stuff.

#Comment Re: made: 2012-03-12 11:05:39.37947+00 by: DaveP

I went with mostly PEX when we remodeled my bathroom (and probably will for the kitchen, as well), but then I don't like making copper joints, so the ability to go around corners decided the issue for me.

The leaching from PEX doesn't concern me too much, as I filter all my drinking water, and once I remodel the kitchen, I'll be filtering all of my cooking water as well.

#Comment Re: made: 2012-03-12 02:02:44.709014+00 by: Dan Lyke

Yeah, I've got no labor preference either way. PEX will take a bit more learning 'cause there are some wacky requirements for labeling for the initial flush-out (if I go permitted). I've soldered up 40+ joint copper systems and had no leaks when I pressurized, so copper doesn't scare me.

But as Larry points out, the switch to chloramines in municipal water supplies make PEX less likely to etch out like copper will in low pH water.

#Comment Re: made: 2012-03-12 01:35:31.566391+00 by: Larry Burton

How's your water quality? Soft or acidic water will cause copper and lead to leech from your copper tubing.

#Comment Re: made: 2012-03-12 01:33:04.399187+00 by: meuon

Copper is a pain to do, but when done with Silver Solder and a mapp or oxy/acet torch, much easier. There are 100+ year copper installs, there are no 100+ year PEX installs.

I've seen you braze bike frames, do the copper. Pex if you need to fix it cheap right now.

#Comment Re: made: 2012-03-12 00:38:15.927561+00 by: Dan Lyke

The problem I'm seeing with PEX is that it leeches MTBE, ETBE and TBA (tertiary butyl alcohol) (California Recirculated Draft Environmental Impact Report Adoption of Statewide Regulations Allowing the Use of PEX Tubing. California's building code has procedures about flushing (and tagging for flushing) to mitigate this.

There are also concerns about various other chemicals, like toluene, but those are moot since that's about leaching from surrounding dirt, and our plumbing will be suspended.

Still digging...

#Comment Re: made: 2012-03-12 00:31:01.589439+00 by: Larry Burton

I'd go with PEX because it is cheaper, easier to install and more resistant to freeze damage and soft water. Just make sure you keep it out of sunlight and it should give you a much longer life expectancy than copper. I've used it for both water and fairly high pressure air and nitrogen and have been very happy with its results.