How Does The Septic System And Plumbing Work?

Have questions about your manufactured home’s septic system or plumbing? Find out where the pipes are, the type of plumbing that’s used and more!

To begin, it’s important to note that plumbing and septic systems in manufactured homes differ slightly from those in site-built homes. You’ll still have a piping system, waste disposal, water heater, pipe venting, and water valves like in a site-built home. However, the main differences in these systems for a manufactured home are:

The water heater must meet federal manufactured home building standards.
The main plumbing lines run under the flooring system.
The main water supply shut off valve in manufactured homes should be in the utility room where your washer and dryer go.

Before we dive deeper into some of the most frequently asked questions about this topic, let’s start by watching this video. It explains how the plumbing in Clayton Built® homes works together to provide you with more peace of mind. The video includes details such as a whole-house water shutoff valve, larger washer drains, and more.

Next, we’ll explore common questions about plumbing in manufactured homes in greater detail.

Who Regulates Plumbing for Manufactured Homes?

The HUD Code governs the requirements for plumbing systems in manufactured homes to ensure proper installation and construction. Local plumbing codes may take precedence over HUD Code regarding the connection of plumbing systems to site connections for septic and water supply. Check with your local home consultant to find out what codes will apply to your plumbing and septic systems.

Where are the Pipes in Manufactured Homes?

Plumbing in manufactured homes runs through the floor. The pipes are located within the belly board, also known as the bottom board, and surrounded by insulation. The belly board encloses the insulation around the plumbing and keeps everything securely in place under your home’s flooring system.

What Type of Plumbing is Used in Clayton Built® Homes?

New Clayton Built® homes feature durable pipes made of PEX plumbing. If you check your plumbing, you will notice two different sizes of pipes. The smaller pipes serve as your water supply lines, while the larger pipes function as drainage lines. Some of the advantages of PEX plumbing include:

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

More About Manufactured Home Plumbing Systems

Plumbing vents in manufactured homes help drain lines by drawing air from outside the pipes. This process creates the proper pressure levels in the pipes for waste to flow. Federal building regulations require all manufactured homes to be properly vented. One type of venting you will find in your manufactured home is a direct vent through the roof (VTR), which allows multiple fixtures to be vented. Both site-built and manufactured homes have clean-outs used to clear clogs. Plumbing code for manufactured homes mandates a clean-out where a plumbing fixture makes enough turns to create a 360-degree angle before reaching the main drain. While the main clean-out is often located outside the home, usually in your yard beneath a sewer cap, you may also find clean-outs throughout the home. Clayton Built® homes typically have clean-outs below each vanity and sink, as well as at the washer box connection behind the access panel. Clean-outs can be positioned in various locations depending on the layout of the bathrooms, laundry room, and kitchen. However, a clean-out will be installed above the floor in these areas and in the plumbing below the floor system for easy access.

What Kind of Drainage Does a Manufactured Home Have?

Manufactured homes have drain lines that extend under the home from the bathroom to the sewer line below the ground. Since manufactured homes are nearly complete when they leave the building facility, the drain lines already extend through the belly board of your home upon arrival at its final destination. At this point, an on-site construction crew will connect the drain lines to your waste removal system, which may be either the public sewage line or a new septic system installed for your home.

Do Manufactured Homes Have Septic Tanks?

Your waste removal system depends on your home’s location. If you use a public sewer system, plumbing will carry waste from your home to the public sewer system. However, if you do not use a public service, you must install a septic system approved by your local municipality. When considering septic systems, the septic tank and absorption field system is a commonly used option. In this case, waste drains from your home into a septic tank buried underground. The installation team will install the septic tank during the setup of your manufactured home. These septic tank systems require periodic pumping, and regular inspections are also recommended.