Cross-linked polyethylene (PEX) is nothing new under the sun. It was developed in the late 1960s by inventors like Thomas Engel and Dow Corning, and marketed to Europe as the next best thing to happen to plumbing and heating since copper.

But in the United States, PEX's momentum is just beginning to roll. It has been used in radiant heating installations here since the early 1980s with success. However, as a viable product for use in potable water systems, PEX has yet to make its stand.

That's all about to change if the PEX market -- and convert contractors -- has anything to say about the matter.

While most people still are unsure about the flexible tubing as an option for their water systems, the word is out there, and market share since 1996 has seen a rise.

A recent survey by Reeves Journal, a fellow BNP publication that covers the western states, shows that five years ago copper held 98 percent of the market, with chlorinated polyvinyl chloride (CPVC) picking up the rest. A few years later in 2001, 90 percent still listed the rigid metal as their material of choice, but PEX was on the scene with 7 percent market share.

Several factors contributed to this jump in percentage. First, excessive failures in the field for polybutylene (PB) installations led to class action lawsuits. Shell stopped selling its resins to the PB market, literally drying up its supply, and leaving the door wide open for PEX.

A bit earlier, though, the rise of PEX for radiant floor heating applications showed the industry was poised to go to the next level. States and contractors that had used PEX in radiant applications saw the use for the polymer in potable water.

With manufacturers already producing PEX for one market, it was easy to translate that business to the plumbing sector.

And finally, an awareness and public interest in safe, healthy drinking water fueled professionals to find a way to overcome obstacles facing corroding rigid pipe.

"Most building owners don't know about PEX as an option," says Don George of Modern Plumbing in Portland, Ore., whose company specializes in repiping with Uponor Wirsbo's AquaPEX tubing and handling high-end remodel jobs. "Once I lay out the pros and cons of both copper and PEX, and tell them about my own home's PEX repipe, that usually sways them to go with the flexible tubing."

Don Sanders of MSI Mechanical Inc., another Portland contractor, currently has a 10-year history of installing AquaPEX without a failure.

"Right now we're using the product in a 25-story building," says Sanders, who believes PEX is his product of choice because of installation latitude. "And we've installed PEX in seven other high-rises up to 20 stories. We've also used it extensively below-grade at grocery stores because of its freeze resistance."

Wirsbo began producing PEX for potable systems in the United States market in 1993. Since that time, the industry has seen hundreds of millions of PEX tubing installed.

So what are the pros and cons of using PEX for potable water systems? Are the benefits solely for the end-user? Or can your plumbing business profit, too?

A Little PEX Education

Metal pipe's inability to stand up to aggressive water conditions has forced several areas of the country into expansive -- and expensive -- repipes. Changing pH levels in the soil also can lead to electrolysis, where stray electrical current can wear down metal pipe prematurely.

"Copper was cutting-edge 50-60 years ago," says Bill Wright, manager of radiant and plumbing systems for Weil-McLain, which markets its Alumi-PEX tubing for plumbing systems. "Now there are those that fear the 'unknown' of PEX in 50 years, so they avoid installing it. But I know what my copper pipes are doing after 50 years -- they're turning green and scaling; and I'm drinking that!"

The federal government's commitment to clean, healthy water almost demands that an alternate piping product be used in aggressive water conditions found nationwide. And PEX passes standards tests with flying colors as the next generation for potable water.

"After the issues surrounding polybutylene, PEX is the most heavily scrutinized and heavily tested material ever to be introduced to the plumbing and heating industry," says Patrick Sauer, vice president of sales and marketing for Zurn PEX Plumbing and Radiant Heating Systems (a division of Zurn Plumbing Products Group). Zurn's second training facility is currently under construction in California, where plumbers have the opportunity to install a complete PEX plumbing system over a three-day course. "We're seeing more and more contractors switching to PEX every day. And as these contractors have success, we'll see the entire industry turn."

The labor intensity of installing copper and CPVC also gives a boost to PEX.

"CPVC and copper traditionally come in sticks -- 20-ft. lengths that you have to sweat and solder or flux, introducing flame to a construction site," offers Dave Laursen, director of radiant and plumbing systems also from Weil-McLain. "It's very labor-taxing. PEX comes in 1,000-ft rolls, and is easier to install with fewer fittings, which means less chance for a leak. The labor, though, is key."

Contractors agree.

"PEX is a saver; it saves me time, which saves me money," George says. "I've often come out days ahead on a job with PEX installations. We can then pass those savings on to the owner."

Savings also can be realized in water and energy when using PEX.

"In a manifold, or home-run system, PEX is faster on hot water delivery and the manifold works like a circuit breaker," explains Marisa Chandley of Vanguard Piping Systems Inc. Vanguard's plastic MANABLOC manifold system has been in production for 12 years. "You can isolate a single fixture; you can isolate a single aspect of a fixture, such as the hot water side of a faucet to change a washer."

An entire system does not have to be drained when repairing or adding on to a PEX plumbing system, unlike a sweat connection.

Some other advantages of PEX are:

• Forgiving to expansion, with reduced water hammer;
  
• Less prone to sweat because it is polymer-based;
  
• Can withstand direct burial in a concrete slab;
  
• More freeze-resistant than metal pipes;
  
• Does not affect taste or odor;
  
• Less jobsite theft.

Feet Dragging?

"Newer contractors and those who want to move in a more competitive market or niche I've found to be open to the idea of PEX," says REHAU heating and plumbing department manager Bill Johansen. "But there are contractors who remember the PB issue a few years ago. Even though PB is a totally different polymer than PEX, it still stays with them."

Johansen also says this fear of the unknown could mean contractors just haven't been exposed to PEX installations in their area yet. REHAU has been in the PEX business for more than 30 years using the European criteria, and started selling commercially to the states in 1990. "We try to smooth over fears of contractors. They're not a guinea pig for REHAU trying to sell a new product. PEX is already a proven product. We're just here to help."

Although PEX is accepted in almost all state plumbing codes, complications with local inspectors could keep businesses from going with something new.

"We were one of the first companies to use PEX in the area," says George. "Back in 1994-1996 there was a bit of trouble with inspection. They were some of the first jobs they'd seen with PEX; it was new technology to them."

Many contractors may think that PEX is not approved by local codes, but check again, says Chandley. "PEX manufacturers have been fighting hard to get PEX accepted in the codes and make clients aware of its benefits. No, we haven't got 100 percent, but we're pretty close."

Wales-Darby Inc., a New York-based manufacturers' rep for Wirsbo said inspectors in their area voiced concerns about the ease of installation that PEX afforded. They were afraid that the plumber would lose business to the do-it-yourselfer and they would do shoddy work.

"We merely ask them when was the last time they stood outside Home Depot and watched how much copper goes out the door," says Greg Talbot, vice president sales and marketing for Wales-Darby. "We also point out the commitment Wirsbo and other PEX manufacturers have to the professional plumber and normal distribution channels."

Other problems PEX faces before it becomes a household name is the feet dragging in general that industry professionals have to change.

"You can't overlook the unwillingness to change. But that's not a bad thing; we all have a certain 'comfort circle,'" says Keith Whitworth of Watts Radiant, who acknowledges that PEX is not a miracle product or a "one-size-fits-all-applications" elixir. "PEX has its limitations, but its advantages far outweigh them. It should definitely be considered for potable plumbing systems."

The Plastic Pipe and Fittings Association, an organization made up mostly of plastic pipe and fittings manufacturers and their suppliers, has worked hard since its inception in 1978 to point out that PEX has met stringent ANSI standards, as well as UPC and international codes for safe use for potable systems.

"There's no reason not to look at PEX as a viable product in the plumbing industry," says PPFA executive director Dick Church. "No material is good in each and every application, but where PEX can be used, it should certainly be an option."

With millions and millions of feet of PEX installed -- and working --in the states today, the "unproveness" of PEX is not even an issue. PEX manufacturers like Stadler-Viega have this to offer in way of advice to installers still on the fence: Try the product of an established manufacturer who has a proven track record and will stand behind you, as there is nothing to lose, but lots to gain.

"I would say at the very least, get informed about all PEX's benefits and give it a try," concludes Ingrid Mattsson, marketing communications manager for Wirsbo. "This is a clean, healthy, quiet and dependable system for your customers that installs fast and easy. If you don't like call-backs, PEX is for you."