Technical Blog

Welcome to John’s Blog. Answers to frequently asked questions are periodically posted here. The objective is to share information about PVC pipe with readers as well as with utilities, design engineers and pipe installers. The blog provides the latest information on PVC pipe design, installation, and application for water and wastewater infrastructure projects.

We encourage you to connect to John’s Blog by bookmarking this page or by connecting our Technical Blog to your RSS feed program.

John Houle: Senior Technical Consultant, PVC Pipe Industry

John Houle holds a Master’s Degree in Civil Engineering from the University of Missouri and an MBA from the University of Oregon. He has more than 25 years of experience in the plastic pipe industry in applications engineering, market development, forensic analysis, technical writing, and standards development.

PVC vs Ductile Iron (DI) Pressure Pipe for Water Mains

Posted By John Houle on Mar 6, 2013

Attached is a two-page comparison sheet that addresses some important issues in water pipe selection and serves as a quick reference for comparing PVC and DI pressure pipe. Click here.

During 70 years of sustained growth for PVC water pipe, iron pipe’s market share has decreased dramatically. The iron industry has reacted by negative attacks and by spreading misinformation about PVC pipe. We thought it was time to provide a more-balanced view.

Health and Safety

PVC is used in over 50,000 municipalities in North America because it meets all health and safety regulations – some 10 million quality tests have been conducted on water carried through PVC pipe since it was introduced. Health and safety are major reasons why most new installations of drinking-water distribution pipe are PVC.

Why the Move from Iron to PVC?

A combination of two factors is driving the move from iron to PVC:

Increased focus on replacement of our decaying and corroding water infrastructure.
Recognition that thinner-walled DI corrodes sooner than traditional cast iron pipe products (See: Utah State University’s 2018 Water Main Break Rates In the USA and Canada: A Comprehensive Study).

Transitioning from Iron to PVC Pipe: A Smooth and Seamless Process

The DI industry has argued that the transition to PVC is so difficult it would be better to stay with underperforming iron. In fact, the typical move to PVC has been smooth and seamless. Here are the facts:

Same outside diameters – for the municipal water market, PVC pipe and DI pipe are manufactured in the same cast-iron outside diameter regimen.
Same fittings, valves, and appurtenances – the same slip-on or mechanical joint fittings, valves, and appurtenances used with DI can be used with PVC pipe in the same manner. This ensures that product styles and installation procedures will be familiar to the waterworks professional.

We encourage you to contrast and compare and to include PVC pipe in your upcoming water project bids. Join the growing number of North American water utilities that are providing greater value for taxpayer dollars by using PVC pipe – installing better-performing pipe while simultaneously reducing capital and O&M costs.