What Size Should Our Water Pipes Be?

We’re building a new home. Does it matter what size our water pipes are?

Yes! The sizing of water pipes contributes to several things, primarily water pressure. While smaller lines may be okay for one fixture, they are not able to supply sufficient water pressure to several fixtures at once.

You want to make sure that water lines that are serving two or more fixtures are properly sized and meet all plumbing codes. Hydrostatic pressure can affect water pressure as well, so it’s important to consider the placement of the pipes while building.

How can we make sure the right sized pipes are installed?

If you are in the planning stages of building your home, you can work with the builder and an experienced licensed plumber to determine what size water line should be used. National and local plumbing codes dictate the size (diameter) of the water supply pipes that are to be installed in residential structures as well as commercial and industrial structures of varying sizes. During the design and planning stages, the architect and builder will deal with sizing water supply lines, drains and the rest of the plumbing infrastructure. A plumber will use a series of calculations to determine the length of the pipes from the incoming main water line and how many fixtures and appliances the system can support. Homes or structures with second (or third) stories may require larger pipes.

We just moved into our new build and at times the water running through the pipes is very loud. What’s the issue?

There are several possible reasons. When the wrong sized pipes are used, the loud sound of rushing water is more apparent. Pipes with a larger diameter reduce the noise because the water has more space in which to flow. However, the plumbing code usually dictates the size of water supply pipes. Using foam pipe insulation on water supply pipes during the building phase can also help reduce noise. Since building is complete on your home, it’s too late for that but you can insulate exposed pipes such as those beneath sinks, to reduce noise.

If you are in need of a professional, Roto-Rooter plumbers and service technicians can provide assistance for residential plumbing-related issues inside or outside of the home.