Designing for performance, not prescription

Walter Vernon

Building codes have a long history, first appearing in Babylon in the ancient Code of Hammurabi, an early set of laws created about 4,000 years ago. Those of us who work in the commercial building industry should be happy that codes continue to modernize, since the penalties for builders who constructed unsafe buildings under the Code of Hammurabi included death.

However, the function of such early codes was basically the same as it is today:  guaranteeing the safe (and sound) design and construction of the built environment.

Unlike the European Union, which is moving toward building code standardization called the “Eurocode,” the United States uses model building codes, which vary greatly by municipality, state and even fire district. In the past, most of these codes dealt with the safety of a structure (from fire, earthquake, safe evacuation routes, etc.) rather than the structure’s efficiency. As energy and water prices have climbed and awareness of climate change has grown, codes in some sectors are now moving toward more performance-based measures that push architects, engineers and builders to create buildings using resources more efficiently.

Industry examples
Some sectors, including the healthcare industry, have been slower than others to adopt more sustainable codes. Under ever-increasing financial pressure, patient protection and infection control has, for the most part, trumped innovative green building technologies more frequently seen in other types of commercial buildings. For example, requirements for items such as air exchange mean that hospitals are sealed and windows don’t open, precluding using any natural ventilation.

However, some healthcare organizations are beginning to use green technologies where they can. Kaiser Permanente, Partners Health and the National Institutes of Health are working on researching displacement ventilation, which uses much less energy than the overhead-air systems normally deployed in hospitals.

Local codes have also influenced more energy-efficient building design is in the construction of data centers. One of the fastest-growing energy users in the United States, data centers consume vast amounts of energy to run servers and require 24/7 power supplies in order to preserve society’s growing amount of electronic data.

Not surprisingly, data centers require more cooling than many other commercial buildings. Many data centers use an outside air economizer for cooling, which utilizes outside air when the temperature and humidity are lower than that of the air inside. This is a very common system used in office buildings and is remarkably energy efficient. Another alternative is a water–side economizer, which utilizes water from a cooling tower to provide free cooling.

While such techniques are required by Oregon and Washington codes, other states haven’t updated their codes to include the technology, even though it’s proved successful in cutting energy use in data centers.

Another way of cooling data centers efficiently is to segregate hot and cold “aisles” from each other by installing physical barriers such as plastic curtains similar to those you see in a grocery store’s refrigerated aisles. This technology is new to data centers and is remarkably energy efficient. While this technique is not required by codes, the potential for cutting energy is so substantial that it is being recommended as a data center “best practice” by California utility Pacific Gas & Electric.

Cracking code
So what’s a green builder to do? How can you bring your building into the 21st century if building codes don’t even recognize the latest energy-saving technology?

First, we need to advocate for incentives and programs to help finance green building in sectors of the economy, such as health care, that are financially hard pressed. It’s the classic guns vs. butter debate that we heard about in undergraduate economics classes. As a society, we are choosing to finance the “guns” side of the equation with choices about military funding. We need to make a few more “butter” choices, decreasing our dependence upon oil and improving our use of clean technologies that save—and even generate—energy.

We also need to use our talent as designers of durable buildings to push clients to use the latest innovations that save energy and water yet still provide occupant safety. In the case of health care, this means unleashing ingenuity in design to provide infection control and healthier, energy-efficient buildings. Some jurisdictions, including California, seem ready to do this; in other jurisdictions, we need to help clients understand that a building can be both safe and sustainable.

Last, we need research that gives us more sustainable technologies for the buildings of the 21st century. The best research currently available is that of public-private partnerships, such as Kaiser Permanente, Partners HealthCare and the National Institutes of Health, that are putting the time and energy into green technologies that have the potential to provide safety and better building performance.

Other forward-thinking work includes that of the newly formed Global Health and Safety Initiative (GHSI), which is bringing forward a research agenda aimed at creating health care facilities that operate with optimal safety for patients and staff while providing maximum environmental benefit. My own firm is working with the Lawrence Berkeley National Laboratory to find ways of better measuring and benchmarking energy consumption in health care facilities. And, the Environmental Protection Agency and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) are working on reducing the consumption of energy of medical equipment. 

Performance vs. prescriptive
As we move ahead, some U.S. jurisdictions are moving toward performance-based measurement for buildings, rather than traditionally used prescriptive codes. For example, California’s Title 24 (which sets out energy efficiency standards for buildings) requires energy performance for a building to be based on the square footage, rather than prescribing how a building should be built.  This means that buildings must perform at a certain level of energy efficiency, leaving a building’s engineers and architects free to design systems that attain such a level in the way they best see fit. Many in the industry see this as the best solution of all: harnessing the power of human creativity to create long-term, cost-effective solutions.

Walter Vernon is a principal and president of Mazzetti & Associates, a full-service mechanical, electrical, plumbing, technology and climate change consulting and design firm, with offices in San Francisco, Irvine, and Sacramento, Calf., and Portland; Nashville, Tenn.; Baton Rouge, La.; and Houston. Mazzetti recently merged with the Nashville-based engineering firm Nash Lipsey Burch, which has offices across the Southeastern United States.