Can you accurately estimate the useful life of your rooftop HVAC unit? How about your windows? Your roof? Chiller? Sanitary waste pipe? Asphalt parking lot?
THE SHORT ANSWER IS YES.
The Useful Life of an asset or a building component isn’t simply a measure of how long an item can last. A proper estimate of Useful Life should be thought of as the timeframe in which an asset will perform its originally intended function without material diminution of performance or service, and with only routine maintenance. Useful Life is a subjective measure that takes into account inputs like varying operating conditions, maintenance rigor, and by the owner’s risk tolerance.
Several organizations publish Estimated Useful Life (EUL) tables which show average useful life measurements for typical building components exposed to ordinary operating conditions. Among these are Fannie Mae, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and the American Hospital Association (AHA).
A useful life measurement from a published table is only a starting point however. It’s unlikely any given asset will “expire” in the year estimated by these tables. Actual useful life will be affected by several variables. Here are a few to be aware of:
Harsh environmental conditions. In coastal areas salt spray will shorten the life of any metal in an outdoor environment, especially ferrous metals. De-icing salt will prematurely deteriorate concrete and asphalt roads and walkways, and will cause exterior metal doors, handrails and other metal components to corrode. Exterior paint, caulk and other exterior finish materials exposed to heavy sun (especially on southern exposures) will not last as long as those in milder conditions. Heavy shade and excessive moisture can also diminish service life of exterior wood components as these conditions tend to promote fungal decay.
Improper installation. We commonly see residential style condensing units (or heat pumps) installed too close together. Condensing units need to have clearance around the outside of the metal cabinet to allow for adequate air flow which is necessary for efficient heat rejection. Manufacturers typically specify 18 to 24 inches of clearance depending on the application. If condenser units are installed too close together, they compete for intake air. The same problem occurs when units are installed too close to an exterior wall or when shrubs are allowed to grow close to the unit obstructing free air flow. Condensing units operating in these conditions will run longer than intended in order to accomplish the required cooling. This in turn results in increased energy costs, reduced cooling performance, and shortened service life.
Heavier than average use. Carpet in senior living communities, for instance, can have a wide range of service life. Carpet in primary corridors of Independent Living buildings heavy wear from walkers and from electric scooters. Carpet in these areas will have a much shorter life than that in administrative offices or other less travelled areas. Excessive foot traffic on a roof can cause accelerated granule loss exposing lower layers to damaging UV rays.
Frequent use of plumbing snakes to clear drains and chemical drain cleaners can deteriorate and damage waste pipe. Cast iron pipe is particularly vulnerable: rust, wear and age make pipe walls thin and fragile. Eventually, clearing obstructions by mechanical or chemical means will become impractical and pipe replacement will be necessary.
Maintenance quality. Routine filter changes are critical for air handling equipment. Bearings should be greased, belts changed and refrigerant fluid levels monitored. Condensate drains should be kept clear. Condenser water should be treated for proper chemical balance. Compressor oil should be checked and maintained. Motors and starters should be checked for proper operation. Failure to perform recommended maintenance on appropriate intervals will reduce equipment service life. But a robust preventive maintenance program can extend Useful Service Life beyond industry standards.
Industry trends. Emerging technology can render an otherwise useful piece of equipment functionally obsolete, if it can be demonstrated that efficiency, performance or output can be materially improved by replacing the asset. Functional obsolescence can also be driven by changing construction standards and building codes, and by changing market demands.
Owner’s tolerance for repair and the owner’s capacity to absorb catastrophic failure. Think of your car. Are you the type to trade in your 2-year-old luxury sedan for a new one because you don’t want to spend your resources on repairs and maintenance? Or do you continue to replace failed parts on an old car beyond what is economically justifiable? Your organization’s tolerance for unplanned replacement and shutdowns affects the useful service life of many assets.
It’s time for self-examination.
- Is your maintenance contractor spending excessive time troubleshooting HVAC equipment that’s more than 25 years old?
- Are you spending more and more capital funds cutting into floors and walls to repair ruptured waste pipe?
- Is excessive money going toward patching your roof?
If you answered Yes to any of these, the Useful Life of that asset may have expired. It’s time to develop a plan for capital replacement.
PREDICT AND PREPARE FOR THE FUTURE. zumBrunnen’s Capital Reserve Analysis involves a thorough evaluation of all capital assets on your campus conducted by our team of seasoned construction professionals. Using our proprietary budgeting software, we develop a detailed capital replacement forecast where we take into account each asset’s installation date, estimated useful life and future replacement cost.
zumBrunnen conducts capital budget planning to help clients exercise sound stewardship of their resources . . .to minimize surprises. . . and to free you up to execute your mission.
If you have questions about how to estimate the Useful Life of your capital assets, contact us for more information about how we can help you develop a customized capital replacement plan.
We Solve Problems By Preventing Them.
About the Author:
Rob Milam is the CEO of zumBrunnen, Inc. He has 25 years of diverse experience in the construction industry. Rob has worked in multiple market sectors and in all phases of construction management. During his career, Rob has worked on a broad range of facilities including senior living, residential, multi-family, industrial, office and healthcare.
Rob Milam
Owner and CEO
