Polybutylene is a material used in main water lines and in household supply systems throughout the metropolitan area in recent years. An extremely flexible and easy to use material, it has been popular with builders elsewhere since the early 1970's and began to come into use locally in the early 1980's. The main water supplies made from this material are usually a heavy blue or (rarely) black flexible plastic and the interior supply lines are usually gray (or possibly silver or black). Both were manufactured mainly by Qest and Vanguard.
Major system failures had already occurred elsewhere when these materials first came into use locally in the early 80's. By 1984, failures began occurring locally. Shearing forces on main supply lines, fitting failure, improperly calibrated installation tools, poor workmanship and other causes were suspected and a variety of solutions were tried without completely solving the problem. Shell, a primary manufacturer of the raw material used in the pipe, stated in a letter that chlorine concentrations above a certain level could cause the material to deteriorate. This level is sometimes exceeded in the Washington metropolitan area and metropolitan Maryland had a much higher failure rate due to chlorine than Northern Virginia. Early installations also used failure prone poly-acetyl plastic fittings at joints and connections and some jurisdictions went so far as to ban it entirely. Today, the resin for polybutylene is no longer available so it is no longer being used in construction. While Northern Virgnina has largely been spared chlorine-related failures, lots of polybutylene has been used in local building and failures have become increasingly common. At present, failures associated with fittings appear to be responsible for the majority of problems locally. These failures can cause significant damage and the cost of repair or replacement can be substantial. For those who do have it we highly recommend the use of some of the automatic water control systems that will help contain the damage in the event of a failure. These are set up so that if you are away and water begins to flow through the pipes all water to the house will be shut-off within minutes of the start of the flow. It can also be set to a "home" setting that will allow 30 minutes of non-stop water flow before the system takes action which should cover even the average teen-ager's shower. These systems won't solve the problem but they can help minimize the damage and are worth consideration.
Two major lawsuits (Spencer and Cox vs. Shell) secured some financial relief for owners of homes with this material. The qualifying terms and amounts of coverage vary.