<P> Most typical single family home systems won't require supply piping larger than ⁄ inch (19 mm) due to expense as well as steel piping's tendency to become obstructed from internal rusting and mineral deposits forming on the inside of the pipe over time once the internal galvanizing zinc coating has degraded . In potable water distribution service, galvanized steel pipe has a service life of about 30 to 50 years, although it is not uncommon for it to be less in geographic areas with corrosive water contaminants . </P> <P> Copper pipe and tubing was widely used for domestic water systems in the latter half of the twentieth century . Demand for copper products has fallen due to the dramatic increase in the price of copper, resulting in increased demand for alternative products including PEX and stainless steel . </P> <P> Plastic pipe is in wide use for domestic water supply and drain - waste - vent (DWV) pipe . Principal types include: Polyvinyl chloride (PVC) was produced experimentally in the 19th century but did not become practical to manufacture until 1926, when Waldo Semon of BF Goodrich Co. developed a method to plasticize PVC, making it easier to process . PVC pipe began to be manufactured in the 1940s and was in wide use for Drain - Waste - Vent piping during the reconstruction of Germany and Japan following WWII . In the 1950s, plastics manufacturers in Western Europe and Japan began producing acrylonitrile butadiene styrene (ABS) pipe . The method for producing cross-linked polyethylene (PEX) was also developed in the 1950s . Plastic supply pipes have become increasingly common, with a variety of materials and fittings employed . </P> <Ul> <Li> PVC / CPVC--rigid plastic pipes similar to PVC drain pipes but with thicker walls to deal with municipal water pressure, introduced around 1970 . PVC stands for polyvinyl chloride, and it has become a common replacement for metal piping . PVC should be used only for cold water, or for venting . CPVC can be used for hot and cold potable water supply . Connections are made with primers and solvent cements as required by code . </Li> <Li> PP--The material is used primarily in housewares, food packaging, and clinical equipment, but since the early 1970s has seen increasing use worldwide for both domestic hot and cold water . PP pipes are heat fused, being unsuitable for the use of glues, solvents, or mechanical fittings . PP pipe is often used in green building projects . </Li> <Li> PBT--flexible (usually gray or black) plastic pipe which is attached to barbed fittings and secured in place with a copper crimp ring . The primary manufacturer of PBT tubing and fittings was driven into bankruptcy by a class - action lawsuit over failures of this system . However, PB and PBT tubing has since returned to the market and codes, typically first for "exposed locations" such as risers . </Li> <Li> PEX--cross-linked polyethylene system with mechanically joined fittings employing barbs, and crimped steel or copper rings . </Li> <Li> Polytanks--plastic polyethylene cisterns, underground water tanks, above ground water tanks, are usually made of linear polyethylene suitable as a potable water storage tank, provided in white, black or green . </Li> <Li> Aqua--known as PEX - Al - PEX, for its PEX / aluminum sandwich, consisting of aluminum pipe sandwiched between layers of PEX, and connected with modified brass compression fittings . In 2005, a large number of these fittings were recalled . </Li> </Ul>

When did they start using pvc for plumbing