Now add the barbed fitting interior dimension restrictions and someone using a fixture or fixtures on a lower floor. Mr. Jones, who paid a cool 500 G’s for his family dream home, was breathing fire!

Unless careful consideration is given to increased line sizing in the distribution network of potable piping systems using PEX tubing, you must avoid long runs that serve multiple fixtures. The preferred method of piping is a "home run" type installation, with each fixture receiving its own line from a manifold. The manifold should be served using larger diameter tubing and situated close to the domestic hot water storage tank. Little or no pressure fluctuations will be experienced, provided you have relatively short lengths of larger diameter tubing installed on the inlet side of the manifold.

Potable water PEX systems are available from many manufacturers. The tubing can be purchased in a variety of colors to aid in identification between hot or cold runs, which can be a benefit when handling runs through concealed areas.

Although some systems rely on crushing the PEX against the barbs via compression rings, others stretch the PEX to receive brass barbed fittings that have the same I.D. as the tubing itself, thereby avoiding additional flow restriction.

PEX is clean and smooth for good performance and offers less chance of having things stick to the interior. It can be installed with no hidden joints or connections; and when installed with a "home run" manifold, most pressure problems can be easily avoided.

There was no free lunch for the builder who avoided the "unnecessary" expense of using a plumber on this job. He had to repipe the home, which involved tearing up floors and opening walls in a house less than three months old. You see, Mr. Jones is a litigator for a large law firm and earns his living in courtrooms arguing cases before juries.

Dave Yates owns F.W. Behler, a contracting company in York, Pa. He can be reached by phone at 717/843-4920 or by e-mail at .