ome of the earliest writings on the subject of architecture, by Marcus Vitruvius Pollio, suggested that architecture should focus on beauty, firmness, and utility.
But the evolution of architecture has embraced many different features of building design and function, including components that greatly impact building occupants - such as indoor air quality (IAQ).
The 1970s energy crunch brought hearty insulation, sealed windows, and minimal amounts of outside air being circulated into buildings. In light of the 1973 oil embargo, national energy conservation guidelines recommended reducing outdoor air ventilation to 5 cubic feet per minute (cfm) of outside air for each building occupant. Many owners of existing buildings reduced outdoor air input to save energy. New facilities were built with low ventilation flows and airtight designs.
Consequently, awareness about IAQ problems boomed in the 1970s and 1980s in response to growing reports of sick building syndrome (SBS). U.S. Environmental Protection Agency documents report a significant correlation between SBS - symptoms typically including conditions such as headache, fatigue, and irritation of the mucous membranes - and low ventilation rates.
It became clear that changes in building design would be necessary.
“Architecturally speaking, we learned a lot from the 1970s design era,” says Patrick Johnson, a principal at H + L Architects in Denver. “We began to look holistically at IAQ and energy efficiency.”
Mark Williams, also a principal at H + L, says, “The codes we use today to design facilities have increased air exchange rates to ensure the air is circulated more often and that we are using more outdoor air. The perfect balance between running a building efficiently and trying to keep the inside as healthy as possible - that’s the real challenge. That’s something we are trying to understand.”
Indeed, changes have been made to the design of mechanical ventilation systems to meet today’s standards, which recommend at least 15 cfm per person - up to 60 cfm recommended in some spaces - according to the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). This standard specifies minimum ventilation rates acceptable for human occupants of buildings.
“Building codes on ventilation have changed in recent years in a trend to improve IAQ,” says Johnson. “There’s growing evidence that there has been a decrease in sick building syndrome. Paying attention to IAQ does make a difference in the number of sick days taken by employees, for example.”
But ventilation has become one component in a larger picture that architects, building experts, and owners are taking note of in an effort to enhance overall quality of the interior environment. In addition to superior ventilation, important factors include smoking bans, carbon monoxide detection systems, controls on indoor pollutants, and use of low-emitting interior products and furniture.
The University of Denver College of Law building is an example of H + L’s recent work in the area of what Johnson calls “holistic architecture.” The building, showcased as the nation’s first “green” law school, has achieved a LEEDTM Gold rating. LEED, Leadership in Energy and Environmental Design, is a green building rating and certification system developed by the U.S. Green Building Council. (See A Primer on LEED, page 58.)
The council is an alliance of industry leaders working to promote buildings that are environmentally responsible. Using cutting-edge strategies for sustainable site development, energy efficiency, water conservation, materials selection, and indoor air quality, LEED provides a specific plan for assessing building performance and meeting sustainability goals. LEED includes a system that offers project certification, professional accreditation, training, and various resources. Participation is voluntary.
In keeping with the University of Denver’s interest in natural resources law, the $63.5-million DU law building project was driven partly by the input and desires of faculty, top DU officials, and DU staff architects. “It was a very collaborative, integrated design process. The people involved really made a difference, and it was a great opportunity because the owner was obviously interested,” says Johnson.
School officials wanted to create an attractive building that would last 300 years, designed to be as environmentally friendly as possible. The building features generous use of natural light, with an atrium and large windows. Water-saving equipment includes low-flush toilets, infrared light faucets for on/off control, and flushless urinals. Motion sensors activate the use of lights throughout the building. Combined, the building’s energy-saving features are designed to use 40 percent less energy than a comparable building. It is built close to public transportation options, and even includes recharging stations for electric cars.
Arthur Best, a professor at DU College of Law, chaired the faculty building committee involved in the project. The LEED certification makes the faculty proud, he says, “because it provides reliable proof that we really did do what we set out to do - create a building in an environmentally conscientious way - and it reinforces the public service nature of our enterprise: legal education.”
Some of the steps taken to ensure the best possible IAQ were simple, Johnson says. “Some of it is just common sense, like carefully covering the ductwork during construction so no dust or debris got in. We also set a lot of time aside for off-gassing of building materials.”
But one of the most significant factors for promoting good IAQ was the selection of building materials. The project team made extra efforts to use products that emit the lowest possible volatile organic compounds (VOCs), which contribute to poor IAQ. “We paid special attention to woods, paints, carpets, adhesives, sealants, and more,” Johnson says.
In the past, sealants, carpets, and adhesives were culprits in emitting VOCs. For this project, Forbo L910 linoleum adhesive, a water-based adhesive with no solvents or VOCs, was used for flooring installation, and Lees Carpet adhesive was chosen for carpet bonding. Both products meet LEED VOC standards. Atlas Carpet Mills and Lees Carpet provided low-VOC carpet. Both manufacturers’ products used in the project meet VOC limits set by the Dalton, GA-based Carpet and Rug Institute’s Green Label IAQ testing and labeling program. The program works by measuring VOCs for specific products; those that qualify are allowed to display the label. Titebond® Solvent Free Acoustical Ceiling Tile Adhesive was selected for ceiling projects.
Wood products chosen for the building were also selected with care. “Formaldehyde is used in processing wood and furniture. We specified products and manufacturers who move away from those things,” says Johnson.
Composite wood products used for millwork and other purposes were produced by Dow BioProducts; its WOODSTALK™ brand is created from renewable wheat straw and polyurethane resin, instead of conventional combinations of wood and formaldehyde binders. Project managers also chose Pyro-Guard® fire-treated plywood, manufactured by Hoover Treated Wood Products Inc. Pyro-Guard treated wood produces smoke that is no more toxic than untreated wood, according to Hoover.
Furniture and office configuration products approved for the law building also met LEED standards, with characteristics such as low VOCs; water-based finishes; trace amounts of formaldehyde; water-based glues; and some recycled content.
The 191,000-square-foot building, which accommodates 1,200 students, was completed and occupied in July 2003. The faculty and staff are happy with the facility, which functions well for research, teaching, learning, and community activities. “In terms of economics, we expect that the energy efficiencies will be a plus for the foreseeable future,” Best says.
In addition to educational facilities, H + L Architects has been involved in the design and construction
of numerous healthcare facilities. Issues surrounding IAQ are amplified in healthcare settings, says H + L’s Williams. “In healthcare facilities, the patient population becomes very important. People are sick. Otherwise, they would not be there. Many have compromised immune systems; they can become very sick based on the environment in the building.”
Williams was heavily involved in the Anschutz Outpatient Pavilion, completed in 2000. A range of specialty outpatient services is offered in this 475,000-square-foot, $119 million facility. The pavilion also has the region’s first Positron Emission Tomography (PET) imaging system, used to detect cancers at early stages and to diagnose other diseases.
The building is a component of the Anschutz Centers for Advanced Medicine, which also includes an Inpatient Pavilion and a Cancer Pavilion. The Anschutz Centers are part of the University of Colorado Hospital system.
For the Anschutz project and other healthcare facilies, Williams says anti-microbial products are commonly used to kill bacteria and protect patients. “We are faced with trying to find products like acoustic ceiling tiles and carpets that are treated so that bacteria won’t grow in them,” he says.
Surfaces in healthcare facilities may be susceptible to contamination by microbes, spills, and splatters. The growth of bacteria and fungi is hindered by anti-microbial products, creating healthier conditions in healthcare settings. Like other interior furnishings, anti-microbial products also emit VOCs, but project managers were careful to off-gas the materials before using them at Anschutz.
Issues like IAQ and the overall interior environment - with regard to patients - are gathering more interest among healthcare providers.
“There is evidence that the environment has an impact on healing, both from the IAQ standpoint to how comfortable patients are with their surroundings,” Williams says. “That research has allowed architects across the country to have a bit more freedom to create nicer environments. It’s an exciting time to be working in the healthcare field.”
