Do Manufactured Homes Come with Plumbing?

All manufactured homes come with complete plumbing systems that must abide by housing code standards. They are complete with supply lines, drain lines and waste lines. The main difference between manufactured houses from site built homes is that the piping often runs underfloor as opposed to within the walls and the piping material is usually made of PEX or plastic.

Image from Everything You Need to Know About Venting for Successful DIY Plumbing Work | Better Homes & Gardens (

Manufactured homes have a complete plumbing system: “piping system, waste disposal system, a water heater, pipe venting and water valves like in a site-built home.”(1)

The only key differences are that manufactured homes’ piping runs beneath the floor, the water heaters must comply with federal building standards and its main shut off valve (or water supply switch) must be located in the utility room (where the washing machine is).

The venting system of manufactured homes is often a vent through the roof or “VTR”. Just as site built homes, they abide by a plumbing code to provide clean-outs for cleaning up clogs.

If you’re living in an old manufactured or mobile home, there may be a lack of clean-out and cut-off valves. The cleanouts are commonly found where the sewer or septic tank meets the waste drain. It’s good practice to have a cut-off valve at every water source (faucet, shower/bathtub and toilet). (2)

As manufactured homes are meant to be ready for move-in upon delivery to your site, its drain lines are extended through the underbelly of your home. These pipes are ready to receive and attach to your on-site construction of a waste removal system. This will be decided early on, depending on the utility service your site provides, whether it’s connecting to a public sewage line or newly installed septic tank system for your home.(1)

Take note that a septic tank also needs regular inspection and maintenance of pumping to keep running smooth.

If your home is connected to either a public sewer or septic tank, water can be thrown into a portable storage tank, which is later disposed of at dumping stations. This is why older mobile homes go for composting toilets, which get rid of the blackwater disposal system entirely. (Note however this option’s viability varies from your local state regulations and may need to be certified by a government body.) (3)

Image from Mobile Home Plumbing (

Plumbing pipes are either metal like copper, stainless steel and galvanized steel; or plastic like PVC (polyvinyl chloride), CPVC (chlorinated polyvinyl chloride), PolyPipe or PEX (cross linked polyethylene). Different materials perform better for certain functions if it’s carrying hot water, waste water or acting as a vent pipe. (2)

PEX is a type of plastic more manufactured home companies are using for their plumbing. It claims to last longer than copper while being less prone to leaks as other plastics.(3)

According to Clayton Homes, this material is preferred for its following properties: (1)

  • Resistance to scale, which is the build-up of minerals such as calcium and magnesium
  • Resistance to chlorine
  • Non-corrosive
  • High heat resistance
  • Easy to install
  • Less expensive than metal piping

So you can purchase that manufactured home knowing your plumbing issues have been taken care of and are ready for move-in… or flushing.


  1. Clayton. (2021, July 22). How does plumbing work in a manufactured home? Manufactured Home Septic and Plumbing | Clayton Studio. Retrieved May 2022, from
  2. Adkins, C. (2022, March 29). Mobile Home Plumbing Guide. Mobile Home Living. Retrieved May 2022, from
  3. Haley, C. (2021, January 21). How does a mobile home bathroom work? Hunker. Retrieved May 2022, from