by: Kevin Nordmeyer, AIA
Published in Iowa Commerce
April/May 2003
Energy
It’s interesting that building in the first six decades of the twentieth century and before were typically designed to utilize daylight to illuminate their interiors. With the oil embargo of the ’70s came an era of energy reduction in buildings through minimizing window sizes of existing and new buildings because of poor single-pane glass technology and through maximizing the efficiency of the building through increased R-values, HVAC systems, etc. For the last 30 years of the twentieth century, most buildings, with some exceptions, have become insulated from the environment rather than engaged with it because of this focus on efficiency through improved lighting, HVAC, and building envelope technologies.

Daylight
The current focus of sustainable architecture is one of engaging the building with nature rather than insulating the building from it. This creates great value for the building owner and the environment. The Iowa Association of Municipal Utilities (IAMU) Office and Training Facility located in Ankeny is an example of a building that is intended to be a filter to the environment. The main strategy for energy conservation in this building is through minimizing the need for electric lighting throughout the day by simply using daylight in all occupied spaces in the building. The IAMU facility, completed in the summer of 2000, has an annual savings of over 50 percent of the energy of an office building of the same size. This is money that is saved year after year for the life of the building. This is design that provides real tangible value.
Sustainably designed buildings need to consider tuned electrical lighting systems. Even through daylight is a primary focus, electric lighting is still obviously needed during evening and night hours or on unusually dark winter and summer days. Controls have been developed to tune the electric lighting to the daylighting scheme. This is done with photo controls and occupancy sensors. The occupancy sensor indicates to the light fixture if there is someone in the room and the photocell determines if there is enough daylight in the room to perform the tasks at hand. If the room is too dark the lights will automatically dim up to the set task level.
Daylight not only helps reduce energy consumption, but it also is shown to increase worker productivity, to reduce the amount of sick days logged by employees, and in two recent studies in California, has shown to improve math and verbal test scores by more than 20 percent over students in schools with minimal daylight. Sustainable design is about providing buildings that give something back.
Building Materials
There is currently an explosion happening in the number and kinds of materials that are considered to be environmentally friendly. Many manufacturers are providing recycled content materials or are providing materials that can be recycled at the end of their lives. Much of this is driven by the need to minimize the amount of material sent to the landfill. An example of these kinds of materials is the cement board siding panels used on the exterior of the IAMU facility. The siding is constructed of waste wood chips bound together with cement. Another project utilizing “green” materials is the Metro Waste Authority office in Des Moines. Lumber made of recycled plastics is used for interior framing members of office walls. Also, recycled wood sheathing is used for finish flooring in the 301 Grand Ave. office building for Renaissance Design Group’s offices in Des Moines.
Materials are also considered for their embodied energy and their impact on indoor air quality. Architects will consider those materials that require minimal amounts of energy to produce, such as concrete block, brick, stone, or wood.
Regarding indoor air quality, formaldehyde-free particleboards are used, for example, so as to not off-gas toxic substances into the indoor environment. In addition, architects are beginning to write specifications that control indoor air quality and construction waste management during the construction process, thus trying to improve the quality of the indoor environment on the day the owner moves in and the days that will follow.
Land
As Iowans we have always been dependent on the land for our survival. The conservation of this resource is as important as any listed in this article. One of the first questions to consider as a building owner beginning a project is to consider developing existing sites or brown fields in lieu of claiming more agricultural land and becoming part of the urban sprawl. Several building owners and their projects illustrated in this magazine have chosen to re-build sites or buildings that were previously developed. RDG and Kent Mauck reclaimed an old auto dealership in the creation of new studio space in Des Moines, IAMU restored land to Iowa tall grass prairie in Ankeny, The Meredith Corporation re-built the west end of the Gateway in Des Moines, and Wells Fargo Expanded in downtown Des Moines in lieu of moving to the suburbs. The West Des Moines Community School District chose to build a new Hillside Elementary school on a downtown site rather than in the cornfields of the western part of their city and the Metro Waste Authority became a major tenant for a developer in the re-building of the Eastern Gateway in Des Moines. It takes these kinds of commitments from business leaders and owners in Iowa cities and the design vision of Iowa architects to conserve our state’s land resources.
Sustainable architecture is all about bringing value to the owner in terms of putting money back in owners’ pockets in energy conservation. This is done by creating daylighted, high-performance structures that improves the quality of life for people, in conserving resources through incorporating green building materials, in improving the indoor air quality of buildings, and in conserving the land and water for future generations of Iowans. Iowa architects are concerned about the environment and have the skills to help design a sustainable future.