Hello. I’m an owner builder doing a fairly complex project alone, with one laborer. I am, however, using a plumber to do the drain and waste lines, and for sure to do the connections of the more complex fixtures. I’m thinking of running the pex myself.
This brings me to my question: can I use pex and if so which kind? Reason I ask:
Becasue the master bathroom waste runs through the living room ceiling trusses, we elected — rather on the fly — to run cast iron so that it would be quiet.
Now I notice that where radiant heat is concerned, you can’t use aquapex and similar potable water pex where there are cast iron parts becasue of rust. Does this apply to my drain pipe, I wonder? And if so, can I use oxygen barrier pipe for potable? What’s in it that I should worry about?
Thanks for any help you can give.
Replies
I don't understand how PEX could contribute to rust in cast iron, but your pex water supply lines would not be connected to the cast iron waste lines anyway, so how could they affect them?
Incidentally, there are shark bite type fittings now approved for PEX as well as PVC and copper, that are expensive, but require no hugely expensive crimping tools and they are easily removed in case of error or last-minute changes.
http://www.johnguest.com
I like sharkbite fittings for repairs and certain tasks like replacing hot water tanks, but even on a small job like the water supply to a kithen and bath I'll go through a good 50 to 60 crimps. The cost of sharkbites would dwarf the cost of a set of crimpers I only have to buy once.
I was told (by the John Guest rep, now that I think of it) that crimpers are very expensive.What do they cost?
BruceT
I bought a combination crimper that does both 1/2" and 3/4" rings for $ 140 (Canadian) several years ago. All the plumbing in new houses except for the stub outs and htw to the wall are done in pex using rings here. Shark bites are only used where you can't get the crimper in or where in the past you would have used a compression fitting. I understand some of the proprietary systems like Wisbro (Sp?) are a lot more expensive.
You made the right choice using the cast iron drain pipe in that situation.
As Bruce said, using pex for the water supply lines has nothing at all to do with your drain lines. The cast iron pipe is exposed to oxygen all the time through the drain.
What you are concerned about has to do with oxygen permeating closed loop heat lines and corroding the cast iron heat exchangers on boilers.
That is why you can't use Aquapex in those situations. Potable water tubing must be certified, and Aquapex is Wirsbo's certified piping material. The only difference between that and their hePex, is that the hePex has the oxygen barrier. It won't hurt to use it for potable water but they do not certify it for that use simply because they already have a cheaper product available for that specific purpose.
Aquapex is the right product for your situation.
THanks. Much relieved. In case you're interested, I'm blogging about my project -- which I'm one year into and hoping to get finished in another....5 months? Maybe 4? It's at http://www.beatricedohrn.blogspot.com
Love the blog....solar clothesdryer...ha!No Coffee No Workee!
Wow! That's quite a project. What beautiful country!! Good luck with the future construction. It looks real nice so far.