Lessons from a green high-rise
A new design initiative in the residential industry called evidence-based design is surfacing, and its benefits may translate to the healthcare industry. Evidence-based design becomes connected to anticipated patient outcomes by being research-informed, i.e., through formal research strategies. The following describes a case in point.
Approximately 9,000 people reside in various high-rise buildings in Battery Park City (BPC), New York. In 1999, the Battery Park City Authority instituted a set of residential guidelines intended to guide the level of environmental performance of its new building program, which will house some 8,000 people. The BPC guidelines seek to increase energy efficiency; enhance indoor environmental quality; conserve materials, resources, and water; and, in sum, contribute to residents' quality of life.
Building 20 River Terrace (20RT), and seven more buildings to follow, will provide an unparalleled opportunity for designers to begin performance studies of environmentally proactive building practices. Some of these sustainable initiatives may help set benchmarks for best environmental practices within healthcare design. Taken category by category:
Energy: All energy-related strategies employed at Building 20RT—whether related to lighting, windows, façade materials, the HVAC system, pumps, or fans—were tested during design through extensive use of the U.S. Department of Energy's DOE-2.1 computer simulation program. Predicted performance characteristics were described in terms of BTUs, kWh, dollars, and payback periods. These simulations also defined the points of measurement for the building's mechanical/electrical systems' commissioning and for ongoing monitoring of building systems.
To the naked eye, the building façade contains only a hint of the sustainable energy practices that went into its design. Most evident is its covering of 50% brick, 39% low-emission glass, 11% (thermally isolated) aluminum frames, and the use of photovoltaics (solar energy) integrated into portions of the west and south façade. Thereafter, CMUs, layers of rigid and bat insulation, extensive caulking, a carefully installed taped vapor barrier, and drywall make visible—but only in computer simulation—the extensive control that the wall assembly exerts over air infiltration and thermal bridging. Parenthetic to the building's design, but of interest to healthcare design, are the large expanses of window and increased daylight availability to tenants—a possible benefit to as many as 50 or more of the building's occupants with seasonal affective disorder.
Planted roofs: Planted roof areas have received a great deal of attention as a strategy to reduce the urban “heat island” effect created by reradiated heat from building rooftops. Plants tend to reduce surrounding temperatures through transpiration, particularly during warm months. It follows that such temperature drops would contribute to reducing the energy use associated with air conditioning. Building 20RT employs these strategies on two roof areas, with the added amenity to tenants of access to the larger planted roof.
Many hospitals and healthcare buildings have terraced or roofed areas that can make good use of landscaped areas for staff and patient access. The environmental benefits of a planted roof could accrue to the area surrounding an urban health facility, but perhaps more importantly, the roof-planting program could be integrated into healthcare facilities as part of access-to-nature programs in the form of healing gardens, rehabilitation areas, and stress reduction locales.
Water conservation and centralized waste water treatment: Water conservation measures are an integral part of all building fixtures and appliances at 20RT. Storm water is collected, treated, and stored in a 10,000+-gallon holding tank for use in cooling towers or for landscape applications. BPC also requires the use of gray water. Gray water systems typically collect bath and sink water, treat it, store it, and reuse it for toilet flushing. But rather than using this approach, a design decision was made at 20RT to install a “black water” treatment facility, which treats all waste water rather than just the bath and sink water. Functionally, a black-water treatment system was found to be a more efficient design response to the requirements for safe water reuse in a high-rise building; the 20RT wastewater treatment facility is the right size for the amount of water needed for the building's toilet flushing, cooling tower water, and landscape irrigation.
This building's integrated system of water treatment, while it has been applied to some regional schools and public buildings, is completely unique to any New York City high-rise building and could be a very effective program for any urban healthcare facility.
Indoor air quality: No facet of building 20RT provided the intersection of more strategic thinking than that of indoor air and environmental quality. All apartments are provided with centrally supplied, filtered, conditioned, and humidified air. Each apartment also has a four-pipe fan coil unit that allows tenants to use temperature control and supplemental filtration. Regardless of operable window locations, kitchens and bathrooms have continuously operating ducted exhausts. To control emissions, no formaldehyde was permitted in any building material, and caulks, adhesives, paints, and finishes were required to meet rigorous Green Seal and California emission standards for volatile organic compounds.
Many of the air quality concerns driving the design of 20RT were evidence-based and are relevant to informed healthcare providers. Consider that government and medical literature indicate that allergic rhinitis, chronic sinusitis, and asthma are prevalent in at least 30% of our population. Add to this the occurrence of atrophic dermatitis, and the number exceeds 40%; with seasonal affective disorder, the number increases to 50%. While many of these conditions can co-occur in some individuals, these discrete percentages should be a cause of concern for anyone interested in environmental and/or client-oriented, evidence-based design. From a proactive point of view, this strongly suggests there are many opportunities to apply or develop building strategies that can significantly reduce occupants' indoor exposure to harmful and irritating agents, benefiting both those in good health and those with a range of chronic conditions. Also, many of those strategies that are good for health can have the added benefit of being sustainable.
It is easy to forget that once the aesthetic veneer is removed from architectural design and engineering, what remains is actually the result of a great deal of research and evidence-based design. The purpose of building design is to meet the need for occupant comfort, health, productivity, and quality of life. But without an abundant quantity of evidence-based research to improve the decisions involved, design becomes slow to respond to changes in those needs. It appears that sustainable and high-performance building concerns, as well as evidence-based healthcare design, can serve as the drivers that bring both efforts into a much-needed, closer relationship with client health and satisfaction. HD
Asher Derman, PhD, is president of Green October, LLC, an independent environmental consultancy that has provided services to the designers of Four Times Square; three “green” high-rise buildings at Battery Park City; and the offices of Scholastic, Inc., Condé Nast Publishing, and AOL Time Warner. He is actively involved in designing and implementing the Battery Park City Authority's building performance indicator program and is a member of the DuPont Antron® Sustainability Advisory Council.
Healthcare Design 2003 November;3(4):10-11