When plumbing PEX for potable water supply do you use a big main manifold and go to each fixture or do you use a smaller main to go to sub manifolds in the kitchen, laundry and each bath?
Also, what’s the difference in PEX and AL-PEX?
When plumbing PEX for potable water supply do you use a big main manifold and go to each fixture or do you use a smaller main to go to sub manifolds in the kitchen, laundry and each bath?
Also, what’s the difference in PEX and AL-PEX?
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Replies
You can do it either way, with one main manifold and individual runs to each fixture, or separate sub-manifolds throughout the home with shorter runs to local fixtures. Comes down to personal preference and what you want to do. As an example, if you wanted to have instant hot water available in a bathroom area, it would make sense to use a sub-manifold and connect the instant hot water system to one of the fixtures in the bathroom.
Al-pex has an aluminum core and is used mainly for heat transfer applications in radiant heating, solar heating, etc.
There's an article in the current issue of Fine Homebuilding p 70 about PEX and your options for running.
You can preview the article and see a video here: http://www.taunton.com/finehomebuilding/pages/fh_180_070.asp
Stace
Edited 6/2/2006 11:01 am ET by SCaseria
BTW Stace... I thought that was an especially well done article. (Meant to drop an email to Andy)
PaulB
I think Andy posts around here sometimes, so he'll see your compliments. On a side note, does anyone else wonder about the long-term health effects of plastics? I mean, on a larger scale, plastic is in contact with our food, our water, and if you've had a medical device impanted, plastic is in contact with all sorts of stuff. The keyboard I'm typing on is made of plastic!The Romans thought lead pipes were a good idea while brake pad manufacturers thought asbestos was a great idea at the time. I don't know. Stace
With the medical technology we have available, I'm sure someone has already done a substantial study on the health effects of different types of plastics. Nothing gets released to the market anymore if it is even remotely hazardous to humans, plants or animals. The important thing in today's world is that not much can be kept secret for long. If something's hazardous, people will know all about it pretty quickly.
I'd say PEX is pretty safe stuff, but I'm no scientist. I'd say it's probably safer in the long term than using metal pipe, either copper or galvanized.
"Nothing gets released to the market anymore if it is even remotely hazardous to humans, plants or animals."Ever hear of Vioxx? Phen-Phen? Silicone implants? Ryan Seacrest? MTBE? You'll even see Teflon come under more scrutiny in coming years.I used to work in an FDA regualted industry where there are layers and layers of testing. But it seems nearly impossible to determine long-term effects and inteactions between different substances from a 5 year study. Also, the way the guys test stuff in labs isn't always the way consumers use products/drugs in the real world.This isn't a "the sky is falling" post, just healthy skepticism.Stace
Yeah, I guess you're right. Unfortunately, the long-term hazardous effects of Ryan Seacrest probably couldn't be quantitatively predicted.
Who is Ryan Seacrest ?
The destination is not the point. The completion is not the point. Enjoy today. If you can't enjoy today, then what is the point ?
While not as hazardous as lead or DDT, Ryan Seacrest is nonetheless annoying. I'd rather take a drink from a lead pipe, than have him over for a drink.To answer question, he's the host of American Idol, has a tv show, and a radio show -- he's the new Dick Clark.
I thought this ryan person was some famous victim of long term exposure to something like shag carpetting, or pet rocks or something...I know what american idol is.It's no wonder I didn't know who ryan seacrest was.I'd burn my telly if I was forced to watch that crap.
The destination is not the point. The completion is not the point. Enjoy today. If you can't enjoy today, then what is the point ?
You're better off that way.
I saw about 3 minutes of that program once.I have heard about it here in various threads.All of which has led me to believe that I'd have to turn off at least 97% of my brain, to be able to stand to watch more than that 3 minutes... ever...
The destination is not the point. The completion is not the point. Enjoy today. If you can't enjoy today, then what is the point ?
Nothing gets released to the market anymore if it is even remotely hazardous to humans, plants or animals. The important thing in today's world is that not much can be kept secret for long. If something's hazardous, people will know all about it pretty quickly.You've got to be joking. Mercury has been in vaccination shots for over 70 years. (You know - the shots we give infants) The took mercury out of pet vaccinations 10 years before they took it out of human vaccinations.How many drugs have been recalled because the are found to be dangerous after being on the market for years?
The Romans thought lead pipes were a good idea while brake pad manufacturers thought asbestos was a great idea at the time. I don't know.
Until we figure how to deliver water without it touching anything, we're stuck with pipes of some type...
Treat every person you meet like you will know them the rest of your life - you just might!
Hi Stace. I don't worry about plastics. Given that our life expectancy is about double that of our grandparents, I don't worry about much <G>.
That said, I'm certain that we know much more about polyethelyne than the Romans knew about lead.
Paul, thanks for the good words.Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom
You know, it's interesting, but the lead pipes the romans used were actually not that bad.In short order they were covered in various mineral deposits, shielding the Romans from the harmful effects of the lead itself.I imagine the first year or so caused some issues, but long term they did fairly well regardless.Just goes to show, I guess.. things are rarely simple.-------------------------------------
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
You wouldn't believe how much lead pipe is still in the potable water system in the USA, your post is correct, its the early use of lead pipe that causes the prob. lots of luck.
Really?When did we figure out lead wasn't so cool, anyway? Sounds like it was fairly recently.. relatively speaking, anyway.-------------------------------------
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
They carp about the possibility of contamination by plastic, I would rather concern myself with where that water comes from. Those water treatment plants scare the bejesus out off me.
NRTRob Wrote: You know, it's interesting, but the lead pipes the romans used were actually not that bad.
In short order they were covered in various mineral deposits, shielding the Romans from the harmful effects of the lead itself.
I imagine the first year or so caused some issues, but long term they did fairly well regardless.
Lead pipe works OK as long as your water basic. If you water is acidic, then the lead leaches out of the pipes. In order to do that the water has to sit in the pipes for some time. Thats why you should run water to clear the lead out of the pipes before drinking it.
The Romans also used lead to sweeten the wine, not realizing the devastating long term effects. That's why you shouldn't keep liquor in lead crystal decanters for storage.
"Also, what's the difference in PEX and AL-PEX?"
Pex Al Pex has an aluminum O2-diffusion layer to keep oxgen out. This quality is of no benefit for potable water.
It also keeps its shape, sags less, and is subject to less movement from expansion and contraction. These qualities might be of benefit for some situations.
Edited 6/2/2006 12:48 pm ET by Snowmon