How to Install Urinal Plumbing

Table of Contents

How to Install Urinal Plumbing

Urinals are a common fixture in commercial bathrooms, and their plumbing requires special attention. The design of a urinal requires the plumbing engineer to consider many factors such as space available, flushing action, aesthetics and ease of cleaning.

Urinal Water Supply Options

A main water flushing system is the most common type of urinal flushing system. It uses water to flush the urinal, and it is suitable for most types of urinals. This flushing system is easy to install, and it is usually used in residential installations.

A cistern flushing system is also an option for urinals, but it is more complicated to install than a main water flushing system. It requires the urinal bowl, brackets and grid waste to be installed, as well as the cistern and sparge pipes. The cistern is often a plastic or vitreous china unit, and it is typically installed behind wall cladding or within a void.

The waterless urinal is an environmentally friendly alternative to the conventional water-flushing urinal, and it is often preferred by building owners and engineers because it is more cost-effective. It can save water and money on maintenance, and it also reduces bacteria levels in the urinal, which helps to keep sewers clean.

How To Install A Urinal

The first step in installing a urinal is to determine the location of the unit. This is important to ensure that the urinal fits correctly in the space, and that it is level with the floor. If the urinal is too low, it will not drain properly, and if it is too high, it may damage the walls.

Urinal Rough-In Plumbing

Roughing in plumbing for a urinal can be tricky, so it’s best to have the advice of a licensed plumber. For example, the rough in must be at least 11.5 inches above the unit to allow for sufficient water supply flow. The rim of the urinal should be at least 17 inches above the floor to meet ADA guidelines.

Urinal Rough-In Diagram

Selecting a Flush Valves

Flushing valves are installed at the top of the urinal, and they release water to flush the urinal. They can be manually operated or sensor controlled, and there should be a regulator that allows the user to turn the lever to control how much water is released. If the flush pressure is too low or too high, the valves may need to be adjusted by a building engineer.

Pipes for Water Supply and Drainage

Using PEX pipes for the water supply lines ensures water can flexibly reach the urinal, however copper can be used as well. The urinal drain pipe needs to be able to withstand constant water flow and corrosion from urine. Copper drain pipes can corrode quickly over time causing plumbing issues, so PVC is recommended.

How To Fix A Clogged or Slow Draining Urinal

If the urinal drain is blocked, it may be necessary to snake the drain with a tool such as an urinal auger or plumbing snake. This tool has a drum and strong cable that fit through the drain and breaks apart blockages. It also has coils at the end that catch debris.

Typically, these tools are available at a hardware store or can be ordered from a urinal company. They come with a handle that can be turned to feed the cable down the drain and are ideal for fixing clogged urinals.

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Casey Loeber

Casey Loeber is the founder of His mission is to share the best information online about plumbing jobs and help plumbers lead fulfilling careers.

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