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Residential Water Supply

Water supply piping brings pressurized, clean potable (drinkable) water to the house from the water meter (public water system) or from a private water system (well or cistern), and distributes this water to all fixtures in the house.

The water supply system includes the water service pipe, the water distribution pipes, and the necessary connections, fittings, control valves, and pumps to bring water to all fixtures in, or adjacent to, a building or premises.

For most of us, our water comes from a municipal water system, where it’s usually extracted from various groundwater sources and treated to remove impurities.

It is then pumped to large water towers that rise above than the highest delivery point in the system.

Gravity provides the pressure that forces the water through the water mains and eventually into our homes.

Whether your water comes from a public utility or a private source, such as a cistern or well, it enters the house under pressure . This pressure allows it to travel upstairs, around corners, or wherever else it’s needed.

The pressure of the water delivered to your home will vary depending on your elevation relative to the source, as well as the complexity and condition of the piping system that delivers it. But once established, the pressure will be constant, and will not change based on demand.

Water stops moving once it enters the house, and flows only when one of the outlet devices (faucet, fixture, appliance) is being used.

House Main
The service pipe (house main) enters the house through the foundation or the slab.

Since the 1970’s, copper tubing has been the most commonly used material for water house mains where water is publicly supplied. Older houses may have galvanized, brass or lead mains.

The minimum required interior diameter for the incoming water line for publicly supplied water is generally 3/4". It may be larger, depending on the pressure and/or number of water outlets (faucets or fixtures) in the house.

Distribution Lines
Water distribution lines carry water from the house main to fixtures and appliances.

In most installations, supply piping branches into a dual system, to provide both hot and cold water.

Generally there are two basic types of residential plumbing (piping) system layouts:

1. Series Plumbed System A series (aka ’looped’) plumbed system means that the water lines go from one fixture to the next, then from that fixture to the next, etc.

2. Branch Plumbed System In a branched system all of the fixtures are connected to a single main distribution pipe (like tree branches). Branched systems are the most commonly used.

There are many variations and combinations of the two types. Even with identical floor plans, there can be a number of variations in how the piping is laid out.

 

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