By Bob Best and Jeffrey Cacioppo
From the November/December 2014 issue
Hidden in plain sight, huge energy savings opportunities can be found in the most visible part of any commercial property—the building envelope.
Savvy facility managers (fms) make it their business to monitor the ins and outs of every building system, from HVAC to lighting to the rooftop—but what happens outside is often another story. Many facilities experts overlook the value in monitoring the performance of their doors, curtain walls, and other building envelope elements, devoting attention to these aspects only every 10 to 20 years or when emergencies arise.
This is a natural mindset since the building envelope takes such a beating from forces largely beyond fms’ control (e.g., the weather), and its components are generally seen as capital expenses rather than operational line items. However, giving up on the exterior is a lost opportunity. In fact, by taking the same proactive approach to the building envelope as is typically applied to internal systems and operations, fms can enjoy improved operational performance, efficiency, and strategy.
From The Roof On Down
As the first line of defense against the elements, the roof is a logical first place to look for energy and efficiency improvements. The common tendency is to replace the roof—at significant expense—every 10 to 20 years, usually because it is starting to leak.
Leaving the roof to fend for itself without proactive maintenance, however, can cut its lifespan in half. Meanwhile, making five or six repairs or improvements during those years can greatly extend roof lifespan at the approximately the same cost as a roof replacement. Furthermore, catching weaknesses early on can make a big difference in mitigating moisture problems or air leaks, which account for 25% of an average commercial building’s energy loss.
In fact, while many assume the only recourse for an aging roof is to replace it outright, some research shows that 50% of roofs being replaced these days do not actually need replacement. For example, in updating the 1990s-era roof of an iconic Chicago building, project leaders made the common assumption that a new roof would be needed simply because of the roof’s age. However, using current forensic diagnostics technologies roofing experts discovered that strategic repairs could extend the life and improve performance of the roof.
Savings Under the Eaves
Of course, what’s beneath the roof counts, too. Curtain walls, doors, and windows account for 35%, 15%, and 10%, respectively, of a building’s energy loss. Simple measures like caulking and weatherstripping are easy, popular ways to control energy loss in many areas around a building. Yet, all too often, infrequently used areas like emergency exits are often overlooked in the quest for energy savings.
The vulnerability of areas where significant air loss is occurring was well illustrated by an energy efficiency renovation undertaken in one of New York’s best known skyscrapers. The project called for below window radiators to be removed, cleaned, and updated with better controls. As the radiators were removed, the project team was shocked to discover daylight peeking through huge gaps in the brick walls where the radiators had been.
An estimated 50% of the heated air generated by the radiators had been escaping through these gaps. Had this important discovery been made earlier, the building’s owners could have avoided significant energy expense over the years.
Using building diagnostics available today, it is not necessary to remove building systems physically in order to find sources of air loss. New monitoring technologies make it much easier to identify areas of energy waste in a building.
With advances in sensors, thermoscans, and aerial infrared building surveys, diagnostics technology can be used to pinpoint heat loss and moisture issues in far more detail than the naked eye can see. A fly-over roof survey conducted with NASA-grade infrared cameras, for example, can capture changes in temperature down to one-hundredth of a degree, empowering fms to pinpoint air leaks, and better mitigate mold, mildew, and moisture. Pressurizing curtain walls and windows to test for air leakage can also indicate what percent of air is escaping through cracks in the façade or leaks around the corners of windows.
Experience also informs monitoring success. Building professionals with proven expertise in using thermoscanning analysis and other state-of-the-art tools will not only know how and when to use these high-tech tools effectively, but also how to evaluate them and make ROI enhancing recommendations.
Data ROI: Benefits Of Thorough Analysis
Like getting bloodwork or an MRI before seeing the doctor, thorough evaluation simply enables better decision making about whether to repair or replace components of the building envelope. It provides a complete baseline assessment and eliminates the need for potentially costly guesswork.
It is true that many analyses will reveal areas that require action, and it is no secret that fixing a façade on an enormous building, recaulking every window on a skyscraper, or repairing or replacing the roof are costly endeavors. But knowing the vulnerabilities and taking action while problems are still relatively small, as opposed to responding to these after they have become full-fledged emergencies, can pay off in several important ways.
Energy savings: A building envelope represents 40% of a building’s energy performance, so it stands to reason that identifying and strengthening vulnerabilities early will reduce energy loss and improve efficiency. For example, a facility management team recently installed a new, high efficiency air conditioning system to reduce energy use by 2% to 3%. When an infrared scan revealed several areas on the roof in need of better insulation, however, it became evident that the building could have been cooled with an air conditioning unit that was half the size of the one chosen, had the roof been corrected first.
Generally speaking, improving the building envelope can reduce the need for air conditioning by 20% to 30%. When the building skin is more efficient, all related heating and cooling systems become more efficient as well.
Budget benefits: Fms can more easily reach operational budget goals with more information to guide their day-to-day management activities, as well as better forecast budget expenditures and improve capital planning. Ongoing work becomes an operational budget item rather than capital investment, an important and beneficial distinction for tax reporting. Plus, it is simply less costly to nip a problem in the bud than to buy new materials or start over from scratch after an unforeseen disaster.
More informed facility management: With better information, fms are also more empowered to fulfill their duties—spending less time troubleshooting or dealing with unhappy occupants, and more time managing operations effectively by making proactive decisions rather than reacting to issues. A problem in the envelope can be addressed early, rather than becoming a costly emergency. To plan a monitoring program, fms can begin with the following actions.
- Take a comprehensive inventory of individual building envelope components.
- Perform diagnostics and surveys of the building, or an entire building portfolio, with aerial infrared scanning.
- Qualify the results with an expert in building envelope diagnostics.
- Analyze the financial implications of the survey findings and remediation strategies.
- Develop a condition-based maintenance plan, rather than replacing components according to their estimated lifespans.
- Measure and evaluate results.
Partnering with a reputable third-party consulting and engineering service company can help ensure an objective and accurate analysis. The more accurate and consistent the monitoring, the greater value fms and other stakeholders will see in terms of energy savings and business decision making. By adopting a comprehensive, ongoing approach to keeping energy in and water out, it might be discovered that the roof and related components don’t need to be replaced after all—and that’s the type of benefit that all can appreciate.
Best is head of energy and sustainability services for JLL, with responsibilities that include new business development, energy reduction programs, client sustainability efforts, performance metrics, operating standards, and training. He is a LEED Accredited Professional through the U.S. Green Building Council and a Green Globes Professional through the Green Building Initiative.
Cacioppo is president and CEO of RAM USA, a provider of roof and building envelope consulting and engineering services. He has more than 30 years of building envelope and systems experience in consulting, contracting, and manufacturing. Cacioppo is a RIEI Certified Roof Consultant.