PEX Fittings

By JAY ROMANO

THE price of copper has nearly quadrupled over the last four years, and plumbers and do-it-yourselfers are taking a fresh look at alternatives to copper tubing and fittings. And what some are turning to is a flexible synthetic material called PEX.

Illustration by Tom Bloom

Andy Engel, a home improvement contractor in Roxbury, Conn., said that PEX is a “clumsy acronym’’ for cross-linked polyethylene, a flexible plastic tubing that has been used primarily for radiant heating since the 1960’s.

In recent years, the use of PEX for potable water — the piping that delivers drinking water to home faucets — has increased by about 40 percent each year.

Copper still accounts for about 80 percent of the market for plumbing systems; other metals and plastics accounting for the remainder. But the recent increases in copper prices, along with growing confidence in PEX, is making it more popular.

“The scuttlebutt among plumbers is that PEX is every bit as reliable as copper, yet costs less and is faster to install.’’ Mr. Engel wrote in the June/July issue of Fine Homebuilding magazine.

While copper plumbing has proved to be quite reliable over the last 75 years or so, it does require some skill when using a torch to solder the fittings used to connect two pieces of copper. And because the copper tubing used in most plumbing applications is rigid, soldered joints are necessary whenever the tubing changes direction.

But with PEX, installation is easier.

“You don’t need a torch,” Mr. Engel said, because PEX connections are made using compression fittings that can be installed with an adjustable wrench or, in some cases, with crimped connections made with a special crimping tool.

And while PEX fittings are typically more expensive than copper fittings, you generally need fewer fittings with PEX.

Greg Lowitz, the president of Builders Websource, a Redwood City, Calif., company that provides advice and resources to the construction industry, said that because PEX is flexible, it can change direction with no need of fittings. It is relatively easy to install a supply line directly from the water source to an appliance using just one connection at each end.

Mr. Lowitz said that the best way to install PEX is to use a manifold, a distribution fixture similar to the circuit-breaker panel. The manifold connects to the main water supply and the main hot water line and then supplies individual runs of tubing to various appliances and fixtures.

The manifold eliminates the “branch line’’ system of conventional plumbing in which the lines to individual fixtures branch off a larger supply line. The manifold system makes it possible to shut off individual supply lines and to add new lines without having to tap into existing lines, Mr. Lowitz said, and it can even save energy by routing hot water directly from the manifold to the fixture.

Mr. Engel, the contractor, said that it is also possible to connect individual PEX lines to an existing copper system by using a fitting that accepts a copper pipe on one end and a PEX line at the other.

And while some PEX manufacturers will sell only to licensed plumbers, he said, do-it-yourselfers can find PEX tubing and fittings at large home-improvement centers and on the Internet.

“PEX is definitely a do-it-yourself option,’’ Mr. Engel said. “If you can make a straight cut and tighten up a nut, you can work with PEX.’’

Source: http://www.nytimes.com/2006/09/03/realestate/03home.html