Inside Iowa State

October 7, 2005

Planners keen on green

by Samantha Beres

When finished, Morrill Hall will be the "greenest" building on campus. In the bathroom, there will be countertops made from recycled glass and stalls made from recycled plastic bottles. In the gallery, floors will be bamboo, an earth-friendly material because it can be harvested in five years, instead of the 15 or 20 years it takes to grow a hardwood tree.

For a number of years, Iowa State has been doing its part to bring the "green design" movement to campus. But it's not just about recycled products and bamboo flooring. Green design is an overall effort to conserve resources like land, energy and water.

Not filling the landfills

"One aspect of building a green structure is to use products that make a building last, as opposed to the disposable approach that a developer might take," said university architect Dean Morton, facilities planning and management (FPM).

Morrill Hall's rubber-tiled roof will last 50 to 75 years. Asphalt shingles last about 20. The tiles will look like the original slate squares that once capped the building but were removed in 1914 because the slate became too heavy for the structure.

"The beauty of the rubber tiles is how light they are," said Kerry Dixon-Fox, FPM project manager. She added that putting slate tiles on would require strengthening the roof structure and using more resources, such as lumber.

"We have such a consumer-driven mentality that we just buy it, use it and throw it away," Dixon-Fox said. "Basically, at ISU we try to plan projects that have no long-term effect on the environment."

Part of that, she said, is to reduce construction waste and track what can be recycled as buildings go up or come down. Old bricks from Morrill Hall have been crushed to become brick mulch. And the ancient drywall (gypsum) will be recycled into leveling compound mixture.

From the demolished Storms and Knapp Halls and the old dairy farm buildings, steel was sent to a metal scrap recycler and melted down. Ninety-nine percent of the 35,000 tons of concrete rubble from these buildings will be crushed and reused.

"I decided early on that that concrete was not going in the landfill," said Mark Huss, FPM project manager. Huss researched what could be done with the rubble. "Once you crush it up, it looks and functions just like limestone," he said.

The concrete from Knapp, Storms and old diary farm buildings will be used later this fall for the base and top material of roads and parking lots at the new dairy facility, a project Huss is managing.

Energy conservation

While the ultimate goal ought to be zero impact on the environment, Morton said, the bottom line for ISU planners is that the campus has as little impact on energy consumption as possible.

Planners for the new dairy farm buildings had this in mind from the get-go. Geothermal energy will do the bulk of heating and cooling for the buildings. Groundwater, which has a constant temperature of 55 degrees, will be pumped from wells and run through a system that generates cool air in the summer and warm air in the winter.

A combination of other energy conserving measures are planned for the dairy project, including additional insulation, energy-efficient windows, better use of daylight for lighting, heat recovery systems (capturing the heat from exhaust air and using it in the building) and timers and sensors on lights.

The result? A 26 percent savings in energy costs, or about $30,000 a year.

Often, energy-saving projects have an upfront cost. Because the new dairy facility qualified for a conservation program through Alliant Energy, a one-time rebate of $69,000 will cover the cost of energy-efficient features.

According to Huss, with the rebate, ISU almost breaks even on energy-efficient measures at the farm.

"But that's not why we did it," he added. "It was planned from the beginning. We're all on board with green design and we implement it wherever we can."

Water management, in the works

The storm water management aspect of green design is one of Dean Morton's favorite topics. The problem: statewide, only about 5 percent of rainwater soaks into the ground. The rest of it runs into storm drains and then rivers, causing them to rise.

"Ideally, you want that water to soak into the ground where it lands," Morton said. "An overall campus plan for storm water management will happen within the next year or two."

Morton envisions systems that catch rainwater that later would be used to flush toilets or water grass. Rain gardens (plots of land with deep-root plants and good soils) would be constructed around campus to absorb water. Systems like these might cost money, but they would replace storm sewer drain pipes which also cost money.

By next spring, the Carver Co-Laboratory greenhouse will have a system that pumps rainwater collecting on the roof to a rain garden on the west side of the building, instead of sending it down rain gutters and to a storm sewer. (Rainwater runoff from the new parking lot west of the Communications Building also will be channeled to this rain garden.)

The new dairy facility will follow water recycling practices that are standard in the dairy industry. For example, recycled water will be used in some of the cleaning and manure flushing operations. Tap water will run through coils that cool the milk coming from the milking parlor. This water, instead of going down the drain, will be used to water the cows. And they like it. When the cows drink the warmer water, their milk production goes up.

"There are lots of little pieces to making green architecture right,"Morton said. "We can't do everything at once, but every project we do has some element of green design."

He added that in time, as this approach becomes a mindset, it will become the norm.

Morrill Hall and ISU's new dairy facility will be registered with LEED: Leadership in Energy and Environmental Design, an organization made up of members from all segments of the building industry. LEED sets national standards for green buildings.