Utilizing PEX Pipe From Street to Fixture

PEX has a high usage rate inside the home, but potential applications extend beyond that

Interested in Fixtures/Materials?

Get Fixtures/Materials articles, news and videos right in your inbox! Sign up now.

After reading at least a couple of my residential plumbing articles, you know by now that PEX is used in more new-home construction than copper and CPVC combined. But you may not know that you can actually use PEX all the way from the curb into the home.

Here are three ways you can maximize the benefits of PEX — flexibility, durability, labor efficiencies, system performance, cost savings — from street to fixture for many, or even all, of your plumbing installs.

Water service

For most single-family residential applications, the main pipeline from the street to the home is 3/4-inch or 1-inch. PEX pipe for potable applications is available from almost any manufacturer in sizes up to 1-inch. In fact, some manufacturers offer even larger sizes up to 3 inches for multifamily, high-rise, or commercial applications.

It is important to ensure the PEX pipe you’re using for the main pipeline is listed and approved for water service. Be sure to check local code and the markings on the pipe to ensure this approval.

Some manufacturers also offer direct connections to the water meter. For example, Uponor offers ProPEX fittings and valves that directly connect the PEX pipe right to the water meter. The fittings and valves are available in straight or 90-degree connections for water meters sized 5/8-inch to 1-inch.

In slab and underground

Some plumbing contractors may be surprised to know that PEX is approved for use in underground as well as in-slab applications. For jurisdictions that allow PEX in these types of applications, this can be a big advantage.

Installing PEX pipe in the slab or underground can help reduce costs because there are no hangers required and less ladder time for installers (adding to installation efficiencies). In addition, no insulation is required, offering even more cost savings.

The pipe is also available with color-coded red or blue HDPE sleeves for removal and replacement of PEX lines, if necessary. Additionally, the ASTM F1960 ProPEX cold-expansion connection is also approved for use in underground and in-slab applications. 

Because PEX is available in long coil lengths up to 1,000 feet, underground connections are rare. But if you need to make a connection, it’s good to know you have approval with the ASTM F1960 ProPEX connection.

Logic layouts

For those familiar with homerun or trunk-and-branch installs, a Logic approach (also called “structured plumbing”) saves significant time and materials. In a Logic layout, the design incorporates multiport tees near fixture groupings to minimize connections and maximize hot-water delivery.

In a typical homerun or trunk-and-branch installation with tees, six regular tees require 18 connections. However, a flow-through multiport tee with six outlets only needs eight connections (six connections for the ports plus a main flow-through inlet and a main flow-through outlet).

With a multiport tee, you’re still able to have six plumbing lines going out from the main line, but fewer than half the connections. And, of course, fewer connections mean faster installs, fewer required parts and better system performance.