Plumbing For Commercial Buildings

Commercial plumbing is much bigger and more complicated than residential systems. Hubbard Mechanical involves more pipes, advanced equipment, and people using the system daily.

There are also more health regulations to comply with. That means that preventive maintenance is more important for commercial plumbing. It’s also helpful for plumbers to have good communication skills and return calls promptly.


When commercial buildings use a lot of water and require reliable drainage, a problem with the plumbing can be a real pain. If you’re a restaurant, service company, or other business that depends on water for operations, a plumbing failure can shut you down for days, costing you money and potentially damaging your reputation. Thankfully, the plumbing systems of most commercial properties are designed to keep operating even in the face of challenges.

One of the most common issues with water supply is low pressure, which several factors can cause. The pipe size is one of the most important, as larger pipes allow water to flow more easily and increase pressure. The height of the building is another factor, as water pressure decreases as it travels upward. In high-rise buildings, booster pumps are often used to increase the water pressure.

The piping material also plays an important role in determining the quality of the water. Cast iron pipes are typically the preferred option for supplying potable water since they are extremely durable and require little maintenance. However, stainless steel is also becoming increasingly popular in some commercial settings. It’s more expensive than other piping types but offers superior corrosion resistance.

According to the ASME A13.1-2020 Scheme for Identification of Piping Systems, all piping should be clearly labeled. That will help prevent contamination from backflow, which can occur when the reverse flow of water carries contaminants into the potable water distribution system. That is especially crucial for buildings with a mixed water supply, such as office, hospitality, and retail buildings. Permanent labels can be applied to the various piping systems to indicate which is potable and which contains non-potable water or other fluids.

Sanitary drainage systems for commercial buildings transport sewage and other waste from plumbing fixtures to the public sewer. In most cases, clean drainage pipes are not designed to be exposed and should remain covered to prevent contamination from soils and insects. However, in some situations, it is necessary to disclose piping to allow for inspection and maintenance.

Whenever the sanitary drainage system for a building is replaced, the existing piping under concrete slabs shall be internally examined to verify that it slopes in the correct direction and is not broken or obstructed. In addition, the sanitary drainage piping in the building must be adequately sized to accommodate the drainage load of the new plumbing. Cleanouts on clean drains shall be located as indicated in Section 708.

The drainage pipe materials for the building’s sanitary sewer, stormwater, and vent, below and above ground, should be selected to be compatible with the piping material used in the main line. For example, cast-iron, copper, or PVC plastic piping are appropriate for building sewers and below-grade drainage. However, uPVC is a more durable material for above-ground drainage.

The sanitary drainage for commercial buildings must be adequately sized to prevent infiltration and inflow into the public sewer system. Infiltration and inflow are especially significant where the sanitary drainage is combined with the storm drain. That requires a more rigorous maintenance program than for separate systems. That includes maintaining a complete inspection and testing program for the cellar, yard, roof, and storm drains to prevent inappropriate connections to the sanitary sewer. In the case of the latter, this may mean requiring the installation of a trapped waste connection with an appropriate-size stack to provide a barrier between the drainage system and the basement of the building.

The plumbing system for a commercial building must manage both the bringing in of clean water and the dumping out of wastewater. It must also provide a way to ensure the safety of those who use it by disinfecting it.

The sanitary drainage system contains pipes that remove fecal matter and human waste from a building’s toilets, sinks, showerheads, faucets, and more. It’s one of the most important components because it keeps a building clean.

Plumbing fixtures should be low-flow to reduce water consumption and lower energy costs. For example, a restaurant should use pre-rinse valves and dishwashers labeled “WaterSense.” These appliances use 20% less water than standard models and offer similar functionality.

Building occupants can also conserve water by regularly flushing all water taps. It’s especially important to wash the water in bathrooms and water fountains after minimal or no usage periods. That eliminates the buildup that may contribute to bacteria growth.

Backflow prevention systems are another important part of a commercial building’s plumbing. The simplest solution is an air gap between potable and non-potable water lines, which forces rising water to leave the system through overflow exits before reaching supply pipe openings. That prevents cross-contamination should there be a back-siphonage or back-pressure issue.

The plumbing system for a commercial building should include a point-of-supply backflow preventer at the water main that feeds the building. This device protects the water supply from contaminants that could cause a backup in the building’s plumbing or contaminate the water supply for a neighboring business. The local backflow agency must test it regularly.

The water main is a key component of any plumbing system. The major artery distributes water to smaller pipes that lead into houses and commercial buildings.

It is also important to remember the type of pipe used, as it dictates the strength and durability of the whole plumbing setup. For example, copper piping is great for a plumbing setup because it can withstand high-pressure levels and is flexible enough to bend around curves. However, it is prone to corrosion if not properly installed and maintained. Brass is another great choice for plumbing pipes, as it has a much higher resistance to corrosion than steel. Its flexibility also makes it easy to thread and manipulate.

The options for plumbing materials for commercial buildings are vast and varied. For example, cast iron is often used in the main sewer line for commercial buildings and water distribution in apartment complexes. These pipes can withstand high amounts of pressure and offer superior fire resistance. However, they are typically heavier and more expensive than other pipes.

CPVC is another popular plumbing material for commercial properties. It is lightweight, durable, and safe to use in extreme temperatures. It’s also able to withstand a lot of stress, which is why it’s often used in industrial settings.

A commercial property inspection should always include a thorough assessment of the water main. That includes identifying the location of the water meter, main shut-off valve, and backflow preventers. It is also important to understand how these components work and their limitations. For example, a building’s water supply system is usually geared toward a specific PSI range that makes sense for its usage and construction. If the PSI is too low or high, it could cause issues with water flow and even damage pipes over time.

The plumbing vent stack, also called a drain stack or sewer vent, regulates air so that water can flow easily through your pipes. It also releases gases from your sewer system so they don’t get inside your building. If you have a broken collar or your vent pipe is clogged, it can cause odors to enter your building and stop water from flowing through the drains. A plumber can help with both problems.

All plumbing systems require a vent to allow waste and sewage to escape into the atmosphere instead of backing up through toilets, sinks, and showers/tubs. A clogged vent stack can lead to raw sewage, wastewater, and sewer gas seeping back into the building through toilets and sinks, giving off a foul odor that can make people sick.

The vent stack connects to all the individual fixtures and branch vents throughout the building, so it must work properly. The building code determines the size of each vent and stack vent, and each vent must have a certain diameter to ensure that it can handle the proper amount of pressure.

In older buildings, the vent stack is usually made from metal such as cast iron or Orangeburg piping and is prone to corrosion. That can lead to holes and cracks in the vent stack that let contaminants into the building. Sometimes, a vent stack may need to be replaced completely to bring it up to code.

The most common issue with a vent stack is when it becomes clogged. Various things, such as improper installation or the wrong size pipe, can cause this. A professional plumber will use a plumber’s snake to break up the blockage and remove it from the vent pipe. They might also use a garden hose to flush the pipe with water and drain the clog, or they might need to remove a toilet and dig down through the floor to get to the vent line in the ground.