Building Systems – Always Phased

By Ben Gries, PE

There is one chance in a building’s life to have all systems addressed at once; that is during its original design and construction. After that point, any renovation, replacement, or improvement will only alter a portion of the original building systems. The HVAC, plumbing, and lighting must agree with the existing structure and architecture. Each system affects the others and needs to be addressed in relation to them, not independently, which can make the changes challenging.

Creating a plan for use is challenging, but necessary to ensure a successful venture. Therefore, it is important to consider the following questions:

  • What is the intended use?
  • What is an acceptable cost?
  • How does that lend itself to possible future uses?
  • How could time affect the current decisions?

None of these questions can be answered definitively. Often occupants make decisions about the building use only to find that they use it differently. The change could be caused by internal or external forces so variables must be considered to ensure an alternative path can be followed. As a part of this plan, it is necessary to consider the systems serving the use.

  • Are the software tools adequate?
  • Is the building appropriate?
  • Are the building systems adaptable?

Many conversations are needed about the use and its ever-changing future to determine the appropriate path forward.

Given that building use is the primary objective, building systems are critical for supporting this function and can be very costly if neglected or unplanned.  Often appropriate systems are selected for the building’s current use, but there is no foreshadowing given to the future use of the building. That is why it is important that a balance is struck during the design and construction of a building. Purpose-built buildings can be constructed more cost effectively than general use buildings; it will serve it’s intended use better than a general use building but will not easily accommodate a change in use. A general use building will satisfactorily handle a variety of uses but will not serve them well. Too often system selections are made, and designs are completed to minimize cost so that money can be spent on the use rather than the systems.

An added complication is that building systems have a finite life. Repair and replacement occur periodically throughout the building’s life and must be planned to avoid loss of use. Change in use can also be planned and implemented over time. Typically, renovations are focused on accommodating the building use; and rightly so, buildings are designed for their occupants and all the building systems are used to serve the occupants, not the other way around. This can be challenging during a renovation. Buildings can only be renovated to the extent that the structure allows. For example, the building envelope and structure have dimensional restrictions. Insulation and glazing systems vary in applicability to the existing envelope. All systems have acceptable and specific applications. Some applications are better in certain situations and others are better in different situations. There is no “right” solution for any given use; there are only “appropriate” solutions and they vary in cost.

All these factors lead to a need for phased system changes or replacements. Planning for these changes helps avoid costly mistakes. The mistakes can culminate as a loss in use, equipment/system failure, or poor system performance – all resulting in expense that could be avoided with proper system planning and phased implementation.