Polybutylene: Bad rap or bad actor?
BY JULIUS BALLANCO, P.E. - Plumbing Engineer
A DOUBLE STANDARD exists for the acceptance of plastic pipe.
Once upon a time the homeowner called his plumber to take care of
leaking pipes. Today he's more apt to call his lawyer first. Then the plumber. Or maybe the lawyer calls the plumber.
Is Polybutylene as bad a piping material as the lawsuits claim? As bad as the TV newspeople report? As bad as the metal pipe manufacturers allege? Of
Polybutylene is perhaps the most tested water piping material there is.
Because of difficulties in gaining acceptance, the Polybutylene industry had to do all of that testing.
True, there have been failures in PB piping systems. But there have been failures in metal piping systems. Nobody's invented the perfect water piping
Having worked as a plumber, I've fixed leaks in all kinds of pipe and tubing:
copper, brass, galvanized steel, galvanized iron, lead, ductile iron, CPVC
plastic.... I'd hate to go to court for every leak I've fixed. I'd spend all my time in court.
The only material I've never repaired is Polybutylene.
PB, like every other pipe material, must be properly installed and used
within its limitations. As with the others, there will be failures. But they're not catastrophic. Much of the negative publicity about PB has been
generated by lawyers and non-PB competitors.
If the television show "L.A. Law" is any indicator, lawyers certainly can
twist the facts in a case. Every plumbing contractor knows why a competitor publicizes failures of the other guy's products.
Plumbing contractors are street-smart enough to realize that everyone -- manufacturers, competitors, lawyers -- speaks half-truths about piping
materials. They emphasize and play up the side of the story that works to their advantage.
PB Pipe is just one of several plastic pipe materials that's been subjected to a double standard. Metal piping, traditionally, has had an easier time
gaining code acceptance. [Aluminum dwv is an exception.-Ed.] Some local codes still don't accept PVC, CPVC, PB, PE or PP.
Politicians often defend their jurisdictions' codes, saying, "We don't want our citizens' homes to have that cheap junk; we want our housing to keep its
high value." Whatever happened to freedom of choice? Why is plastic pipe always referred to as cheap junk?
One plumber told me plastic pipe is considered cheap junk because we remember the cheap plastic "Made in Japan" toys we had as kids.
The analogy seemed appropriate until I thought about what "Made in Japan" means today.
Plumbers and the public in general should equate "plastic pipe" with high quality and good performance.
We don't question use of plastic in other products. One of the most sought after cars, the Corvette, has a plastic body. We prefer plastic skis to those
of wood or metal. The same goes for boats, canoes, eyeglasses, even park benches.
In evaluating plastic pipe, consider it the way you would metal pipe. What are its pluses and minuses? It's the performance of the pipe that should
determine its acceptability.
I often wonder what it would be like if history were reversed. Imagine if
plastic pipe, joined with strong solvent cement forming a homogeneous bond, were the only accepted piping material.
Now suppose the copper industry came forward and said, "We have this new pipe. To join it, you clean it, add flux, heat it to over 400°F, and add
solder. When it cools, you have an acceptable joint.
Imagine the questions the plastics-oriented code bodies would ask:
Does the joint form a homogeneous bond? What if you touch the pipe when it's hot? Can't the solder crack? How can the joint be inspected? Can't the
plumber get burned? Isn't it dangerous if the solder drips on the plumber? What happens in a corrosive environment? Could the acetylene tanks explode?
Should a plumber be carrying pressurized gas on his truck?
Or, to go one better, imagine the cast iron industry coming forward with a
new pipe called extra heavy cast iron pipe. A lO-ft length of 4" pipe weighs "only" 160 lbs. It has a bell hub at each end. To join the pipe, you pack a
hemp rope in the joint, force it down tightly by beating it with a hammer and some special tool. Molten lead then is poured over the hemp rope to hold
it in place.
"You want to pack the joint with what!?"- The author, president of JB Engineering and Code Consulting,
is a registered engineer in Illinois, Indiana and New Jersey and a licensed master plumber in New Jersey.
Shell was the manufacturer of Polybutylene resins in the U.S.
DuPont was the manufacturer of Delrin - the acetal material for older P.B. plumbing joints
Frequently Asked Questions
Q. "I purchased some 1/2" and 3/4" pipe, but I'm not sure how loose or tight they should be. How should I tighten the nuts on the couplings?"
A. Tighten until they squeak, and turn a 1/4 turn more. Don't over tighten, and you'll have a connection that will last trouble free for many years and can easily be taken apart and reused.
Q. "Can I use the above fittings to mix copper, PEX and Polybutylene pipe?"
A. The above Qest acetal fittings fit over copper, cpvc, PEX (crosslinked polyethylene) and Polybutylene pipe. They have a stainless crimp fitting and an acetal compression sleeve that fit over any of those pipes. You can have copper on one side and cpvc on the other side of the fitting, etc. They are very easy to use. They are more bulky than the old insert fittings and for tight places they might not fit or work.
Q. "When did Polybutylene become unavailable?"
A. Shell Chemical Co. no longer supplies Polybutylene resin for pipe applications in the United States that was effective April 16, 1996.
Q. "I get confused about CPVC sizes. What type of CPVC pipe do these fittings fit?"
A. There are two "standard" sizes in CPVC, and this can be confusing. There is the size that matches the outside diameter of copper, which is called "CTS-sized". This is the type of CPVC that we offer, and that's the size that these QEST fittings will fit. With these fittings, you simply add 1/8" to the fitting size to determine the outside diameter of the pipe that will fit. (For instance, a 1/2" QEST fitting will fit CPVC pipe that has a 5/8" outside diameter.) PLEASE NOTE: The other type of CPVC pipe is the same size as steel pipe, which is known as "IPS-sized"; these QEST fittings will NOT compress onto IPS-sized pipe.
Q. "What is your opinion of Polybutylene?"
A. Due to us potentially getting dragged into a lawsuit we cannot really give you our opinion. Here is our founder's personal view (this is his opinion only, and not to be taken as advice or viewed as in any way him/us promoting or encouraging the use of P.B.). He is talking to myself here, and is not giving advice about P.B.:
"If I have up to 1 ppm of chlorine in my water, and if I only have copper or brass insert style fittings, and if I only had copper rings then I'd love P.B. piping for my own house. Of course it would have to be installed correctly and with as few fittings as possible. I have seen lots of defective copper, CPVC, PVC, ABS, galvanized piping, etc. but that was not the fault of those particular products either."
From what I have seen in my many years in the plumbing trade (has taught 10 College Plumbing Courses, been a Plumbing Contractor till 1977 and for over years a plumbing distributor), I believe P.B. has had problems. Some insert style acetal fittings have failed. With high concentrations of chlorine in the water there might be a potential problem. With aluminum rings there also might be a problem.
Polybutylene has some major good points as well:
Less water hammer, resistance against freeze damage, insulating qualities, it's quieter than metal piping.
Q. "Are the above repair fittings to code?"
A. These fittings work great but are not code in many areas. In some areas they are code but in most they may not be used in walls (as with most compression like fittings).
Q. "What is your opinion regarding the future supply of Polybutylene?"
A. Until the end of 1998 we thought that unless Shell changes their mind, there was absolutely no chance of anyone selling Polybutylene in the United States for potable water. In early 1999 we received an email from someone who wrote (but we do not know if this has any truth to it): "Shell has passed the resin to Montell in Belgium. Shell owns 50% of Montell but are selling the share back to Montell." If this has merit then possibly there is a chance that P.B. will someday become available in the U.S. We do know that there are many people who love this piping product.