3.2 Fittings for Water Service Piping
Although a variety of pipe and fittings have been used for water distribution over the years including copper, galvanized, lead, asbestos, brass and some plastics to name a few. As Plumbers we know that some of these examples are no longer permitted to be used by the National Plumbing Code. Section 2.2.5., 2.2.6., and 2.2.7. located in the notes section of the code will show what piping materials are permitted to be used.
Please note that some materials will have a small number in brackets, these numbers refer to notes located at the bottom of the table located on Page 2-77 of the National Plumbing Code.
You will see that Polyethylene water pipe and tubing are permitted for water service underground but this particular pipe is not rated for hot water meaning that a check valve should be installed as soon as the water service pipe enters the building to prevent hot water from the building to be pushed back through the water service pipe due to thermal expansion or backpressure.
The fittings below are all copper but are just to demonstrate some of the different types of connections available. For the purpose of this course pack I have chosen flared, threaded and compression fittings. The specific fittings shown below are all approved for underground use.
Take some time to review these pages in the code and become familiar where to look to find out what pipe is permitted and what pipe is not.
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Image Credits
- Mueller Co. (n.d.). H-15400n. https://www.muellercompany.com/water-works/service-brass/service-fittings/copper-flare/h-15400n/
- Mueller Co. (n.d.). H-15538N. https://www.muellercompany.com/water-works/service-brass/service- fittings/threaded/h-15538n/
- Mueller Co. (n.d.). H-15387N. https://www.muellercompany.com/water-works/service-brass/service- fittings/service- tees/h-15387n/Image Credit