From the outside, Renaissance Design Group’s office at 301 Grand Ave. looks like the average brick building from 1908. Only slightly enlarged windows and a shining silver room branching out of one wall give a hint of the structure’s interior.

Inside, the building looks nothing like it did when it first opened. The outer brick walls and ceilings are supported by rugged wooden beams. The interior walls are gleaming glass. Slatted metal stairways and ramps cut through the air. The 100-year-old structure and its postmodern interior create a striking juxtaposition of styles.

Kevin Nordmeyer, an architect and the partner in charge of design for RDG, helped conceptualize the space. When the company needed a new office, instead of creating a new building, it decided to reclaim an existing structure, adapting it to contemporary needs.

Nordmeyer said it was one of the greatest challenges the firm has ever faced. Clients usually tell architects about their needs and the architects respond. For a group of architects to debate their needs is more difficult.

Nordmeyer’s passion is sustainable design, which minimizes a structure’s effect on the environment. He says buildings account for 30 to 40 percent of world energy use and the same percentage of the world’s wood consumptioneach year. Simple steps can be taken to improve a building’s environmental effects.

Those include building vertically to use less land, employing proper landscaping techniques and selecting ecologically responsible building materials, including certain types of concrete, recycled and recyclable materials, and materials that don’t release chemicals that damage indoor air quality.

He also says building owners can save money by constructing energy-efficient facilities. These structures utilize indirect sunlight and are designed so they stay naturally cool in the summer and warm in the winter.

“It’s not that scientific,” he said. “We design buildings to be a filter of the environment. For years, people have been designing buildings that were insulated from the environment, cold and dark. In the 1800s and before, people knew that they needed thick walls for insulation and windows for light and natural ventilation. It’s common sense. We’re just combining high technologies with low-tech understanding.”

For example, in RDG’s office, natural light provides sufficient illumination most of the day, but the overhead fixtures have sensors that cause them to come on automatically if the room gets too dark. The building also has sensors that determine whether a room is occupied or empty and adjust the temperature and lighting accordingly to save power.

Nordmeyer has been with RDG for seven years. Before that, he worked for West Des Moines-based Wells Kastner Schipper with Doug Wells. Wells had taught at Iowa State University, where Nordmeyer received bachelor’s and master’s degrees. Nordmeyer recently taught a graduate-level course at the university.

Although he works to expand his firm’s use of sustainable design, Nordmeyer has a much broader goal. As chair of the American Institute of Architecture Iowa’s committee on the environment, his goal is to ensure that every architect in the state is able to create environmentally sustainable projects in the next five or 10 years.

He says the resources are out there for architects and for consumers. In fact, to get the best results, before contacting an architect, he recommends that companies consider their organization’s needs, conduct research and ask lots of questions.

“Most architects appreciate the challenge,” he said. “It makes the process more fun and the project turns out better in the end.”

Local projects by RDG include the Lutheran Church of Hope in West Des Moines, the Iowa Association of Municipal Utilities building in Ankeny and the interior of the Equitable building.

Future projects include a sustainable-design restoration of Morrill Hall at Iowa State University, the conversion of the Spalding automobile factory in Grinnell into the Iowa Transportation Museum, and the Trees Forever headquarters in Marion.

“[Trees Forever executives] want the highest level of sustainability possible,” Nordmeyer said. “It’s really thrilling.”

Nordmeyer’s favorite parts of being an architect, he said, is the first part of any project, when he puts people’s dreams on paper, and after the project is completed, when he sees it for the first time with a happy client.

“When they say, ‘It’s more that I expected,’ it’s fulfilling to hear that,” he said.