Commercial buildings are complex environments. Within them, water, HVAC, gas, and electric systems work separately and together within the building’s smaller ecosystems. Some of the building’s rooms are in shaded areas, some in full sun. Some systems were originally calibrated in the summer, some in winter. To further complicate matters, the humans who occupy buildings have differing needs. All of this means that buildings’ systems are bound to lose efficiency over time. And, when they do, things can get expensive. Enter retro-commissioning.
We’ve sung retro-commissioning’s praises before, but they’re worth repeating. This time, we sat down with Jim Schafer, Project Services Energy Director for PRIDE Industries, who detailed how it translates to cost savings that property managers can put back into their buildings.
First, a review of the basics:
What is retro-commissioning?
Jim Schafer: When a new building is constructed, it’s equipped with a variety of complex systems—from HVAC to electric. To ensure the systems are working correctly and efficiently, the building will undergo a “commissioning” process that includes installation, testing, and implementation of these systems and their sequences of operation. But that doesn’t always happen. “Retro-commissioning” is the same process applied to existing buildings—typically five years old or more.
How does this differ from retrofitting?
Jim Schafer: Retro-commissioning is a more holistic approach. For example, retrofitting tends to be more geared toward replacing equipment. This could mean exchanging conventional lights for LEDs or replacing HVAC pumps and motors. Retro-commissioning may include equipment upgrades, but it also focuses on honing processes and protocols to renew what’s already in place.
When is it time to consider retro-commissioning and why?
Jim Schafer: Once a building gets to be three to five years old, heat, air, water, and gas systems start to fall out of tune. Instead of pre-programmed systems efficiently managing themselves, engineers now must step in and manage equipment manually. Let’s say they turn up the heat a few degrees. Someone else might step in and make another manual change to cool things down a few degrees. Eventually, this will lead to system inefficiency, which means high utility bills. Over time, this will finally lead to system failure.
The same thing happens with water and gas systems. Every time a new building is commissioned, its systems are calibrated to operate under the conditions of that day, season, and year. Those conditions change over time. Case in point: California’s recent wet spell. A system commissioned in March 2019 won’t meet the needs of March 2023. Inefficient systems guzzle energy, resulting in high utility costs. They also break down, resulting in costly downtime that could have been avoided. Finally, tenants will be uncomfortable, and uncomfortable tenants won’t want to stay.
What would retro-commissioning look like in these instances?
Jim Schafer: Engineers would investigate the equipment’s original design—the original intent of a building’s various systems, as far as operations within the building environment. After testing each, they would analyze their findings and then discern an updated sequence of operations (SOO) for each system. Then, they would program the various building automation systems (BAS) and building maintenance systems (BMS) to this updated sequence. They would also know what rebates were available and how to factor them in. It’s all a delicate balance, but, when done right, the benefits are numerous.
What are the benefits of retro-commissioning?
Jim Schafer: Many. Improved system efficiency, leading to extended equipment life. Overall improved building operations. Fewer service calls. Occupant comfort, leading to retention. Updated documentation regarding building systems. Ultimately, what’s most attractive is the overall money saved over time, which can be turned back into the business.
Does it benefit a property manager to consider retro-commissioning purely for sustainability reasons?
Jim Schafer: The short answer is yes. A smaller carbon footprint is becoming increasingly important to sustainability-minded customers and investors. Also, for reasons of sustainability, state and local municipalities, as well as federal agencies, offer rebates for several retro-commissioning measures. Substantial water rebates alone, including those for cooling towers, reduce or even eliminate up-front out-of-pocket costs. There are also programs that pay building owners back for the kilowatt hours they save.
What kind of savings can property managers expect from retro-commissioning?
Jim Schafer: It really depends on how far in decline their buildings’ systems are. In general, reduced operational costs and savings associated with equipment life expectancy can be substantial. Calculating the cost benefits to energy savings ratio is key to a positive ROI.
Beyond cost savings, what are the additional benefits of retro-commissioning?
Jim Schafer: The comfort and safety of occupants, definitely. And tenants who feel safe and comfortable will want to stay, thereby reducing the high cost of turnover. And its’ certainly a high cost, including lost rent income, cleaning, cosmetic repair, marketing to attract new tenants, and other administrative costs. It’s always a best practice to keep good tenants, and it’s just the right thing to do.