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How To Maintain Water Pressure in High Rise Buildings

High-rise buildings are becoming increasingly more popular within the United States and that trend is only going to continue. According to a 2019 article in The World Property Journal the average apartment building, in the 1990’s, was 3 floors high, then 4 floors high in the 2000’s, and then rose to 6 floors high in the 2010’s. This trend and type of growth within high-rise construction presents a number of economic opportunities for builders, but with all opportunities, challenges are presented as well. Whether the high-rise building is being used as apartments, offices, hotels, retail or a combination of all, there is no escaping the fact that the larger the building, the more complex and powerful the mechanical system needs to be. 

One main area that demands attention is the water supply within the building, and how it’s transferred from floor to floor. To be up to code, the water pressure within a high-rise building cannot exceed 80 psi. This can create a challenge to ensure the plumbing fixtures (example being a shower) on the top level of the building have enough water pressure to operate as designed while not exceeding that 80 psi limit on the lower floors.

In order to accomplish this, a system and design must be put into place to effectively disperse the appropriate pressurized water to the different floor levels.

High-rise water pressure solutions

There are several ways to solve this problem, methods that have been around for over a century and newer, recommended, approaches. The solution you put in place will depend on the building, but will require the use of a simplex or duplex water booster pump.

Method one. Rooftop reservoir.

The first method, which has been around for over a century, is to utilize a booster pump that will boost water up to the roof of the building into a rooftop reservoir. The rooftop reservoir will then use gravity and other plumbing systems to run the water down to the floors that are located at the bottom of the building. 

However, using this method can create an excess amount of pressure driving down to the lower floors. As the water runs from the top to the bottom, the pressure will increase as the water flows. To help reduce the pressure to an appropriate psi level pressure reducing valves will need to be installed. We typically see this solution used in older buildings that do not have newer mechanical systems.

Method two. Multiple booster pumps.

The second method, which is our recommended approach, is to use multiple booster pumps that are located at different interior levels of the building. You will have a simplex or duplex booster pump in the basement, or ground level, that is pushing water to lower floor levels. Then, to maintain a healthy psi for the higher floors, there will be a second mechanical room halfway up the building. This second mechanical room will have another set of booster pumps boosting water to the higher floor levels. Having two smaller systems designed like this is a cost-effective option that can save you thousands of dollars as opposed to having one large system at ground level.

Maintaining healthy water psi levels is not only extremely important for the patrons of your building, but required for your high-rise building to effectively operate. If you currently have a high-rise building, or are in the initial construction phases, be sure to get in touch with the Towle-Whitney team and we will have a consultation with you regarding best practices for your use case.