I’m considering purchase of a home with radiant floor heating using polybutylene pipe. Everything I’m finding says polybutylene will deteriorate no matter what, but I can’t find anything that says it deteriorates when used for radiant floors. One web site I saw said it did okay in floors, but I question if it fails when used for basic plumbing, it seems like it would also fail in radiant floors. What do you plumbers and other contractors have to say?
Thanks for the input.
Learn more about the pros and cons of single-room ERVs.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
Everything I've read says it has long term problems with RFH.
I am not seeing it fail yet but the lack of an oxygen barrier is causing problems with the rest of the system. If you buy it follow these steps.
1. Isolate the PB tubing from the rest of the system via a heat exchanger.
2. Use only brass or copper parts on the PB side (use a water heater expansion tank instead of a hydronic one on this side)
3. Flush the entire system and get your water tested. Then treat your system with the appropriate chemicals.
Hope this helps.
Edited to add: I am not saying it has no problems. I am just saying I am not seeing the tubing fail here in CO.
Edited 10/23/2003 1:45:39 PM ET by Wet Head Warrior
Ditto what Wet Head said. I would be concerned about layers of sediment in the tubing that will reduce the heat transfer.Unless the house is a good deal, I would be concerned about long term problems.
The grey plastic fittings definitely always fail.
If I remember correctly it was the fittings that failed, not the pipe. Anyone know?
The scientific reports were that it was the fittings themselves and not the pipe.
Also, it was certain fittings manufactured by a certain company, using a particular formula. Not all fittings manufactured are destined to fail. Some pipes were not even joined with plastic fittings.
Actually a decent material with a really bad legal/PR problem leading to its demise. The real rate of failure was not that bad. Profiteering on the part of lawyers and competitors was a big factor. How many steel pipes have you seen fail? How many badly done copper joints? How many eroded copper pipes? Do the copper manufacturers get sued out of business? Once 60 minutes got into it, the result was predictable, and I believe 1996 was the last year of production.
Your insurance company may not cover damage from PB leaks.
Even if you did have the defective fittings, you may have an important advantage with a closed heating system because the deterioration is said to be caused by a reaction with byproducts of water clorination. A closed system rarely sees any fresh clorinated water.
Other plastic materials bear the 'burden' of the PB debacle in the form of slow acceptance by the market, code officials, and regulators.
csnow i think hit the main point of the subject, i recently got certified to install pex tubing from wirsbo, the class was given free to contractors by the manufacturer,(wirsbo) to make sure they install the product correctly. the instructor said just as csnow did that it was the chlorine that caused the failure. apparently they tested for quite some time under all kinds of adverse conditions, but with water that had no chlorine in it. when it got to the field the chlorine quickly deteriorated the pipe much to everyones surprise. if this is true then it stands to reason that the fittings are not subject to failure unless they too are polybutylene.
as a potential homeowner you may be able to find a solution that will preserve this material, distilled water me thinks, and get a bargain on a home that has a suspect material in use for the radiant heating system.
My understanding is that the earliest incarnation, with the plastic crimp bands and plastic fittings, failed at the fittings, the next iteration, with metal crimp bands and plastic fittings (or vica versa) also tended to fail, but the final version with metal fittings and metal crimp bands perform OK.
There have also been problems with it when used with high chlorine content water.
I haven't seen any reports on what encasing it in concrete does to it, though.
_______________________
Albert Einstein said it best:
“Problems,” he said, “cannot be solved at the same level of consciousness that created them.”
Your mileage may vary ....
Thanks to everyone who replied. Further research has convinced me that Polybutylene pipe will always fail. It is just a matter of time. This pipe has not been available in the USA since 1987 and is the subject of class action lawsuits.
I strongly disagree with your conclusion. I have not seen anything that would prove this.
Now, if you are saying that systems with plastic fitings will all fail you may be right. But to say that all PB pipe will fail is just not true.
Sounds like the polybutylene pipe controversy is still alive. Everyone made some good points. My concern with this system is that it is not a closed loop system. New water is continually introduced into the system and it is tied in with the domestic hot water. Latest info I found was that the pipe does indeed fail like the fittings albeit at a slower rate. Since new water is being introduced I think there is cause for concern. Also until I buy the house I don't have a problem. Once I buy it I inherit all problems. That leads me to want to error on the side of caution. An internet search under "polybutylene" gave me some good info. Another concern is the lack of an oxygen barrior with this pipe. That may make the boiler prone to premature rusting. Another question is that should I buy it,and have a problem, how will insurance handle a water problem that affects the slab. With all the concerns about mold these days I would hate to have problems that could affect future resale.
I have heard that Poly is still available. I assume that it is manufactured overseas and has addressed the earlier issues of degradation and lack of an oxygen barrier.
Based on the information you just provided, I would only buy this house with the assumption that the heating and plumbing systems would need to be replaced.
When you talk about the pipe failing slower than the fittings you are correct IF fresh water is being introduced. But you already realize that. You sound intelligent and I am sure you will make good choices.
Of course, you could go a different route with the heating system if you needed to.
Best of luck to you and let us know how it turns out.
Decided not to buy into problems and have backed out of the house purchase due to the PB pipe as well as other problems. Latest information I heard was that sellers were spending in excess of 10K to change the downstairs from radient floor to water heated baseboard heat. I think they were totally unaware of the severity of the problem. Interesting note was that one of the heating companies offering bids said they did the origional work back in 1987. At that time they said copper pipe would have only cost $400 more. Goes to show that cheap can be costly in the longrun.
good move there. Unless the house was so cheap it was worth the expense AND the bother you would regret it.
even soft copper will bust up your slab