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The original warehouse was virtually windowless, but the architects converted the former truck dock openings into windows then punched similar 10-foot (3-meter) openings throughout the facade and fitted them with low-emissivity glass. Perhaps the most noticeable external change from the outside is a steel-and-glass entry that literally reaches out to welcome visitors.

All these windows and clerestories, combined with new skylights, now bring daylight to 75 percent of the interior space, reducing the need for electrical lighting. Light sensors automatically trigger the electric lights when daylight is insufficient. The windows are operable to promote natural ventilation.

Efficiency through Reuse

Despite opening up the facade for light, the scheme still reuses of 76 percent of the original building shell. This efficiency of preserving existing construction earned the project further LEED points. The architects found 10-foot- (3-meter-) long Douglas Fir beams in the old warehouse and reused them in constructing the new mezzanine areas. They reused the existing concrete slab as the building's main flooring. It was dyed and polished to achieve a distinctive patina.

Construction included extensive use of materials with recycled postconsumer and/or postindustrial content, such as cocoon insulation (80 percent recycled content), tile (50 percent), carpet (10 percent), and suspended ceiling tiles (27 percent). Steel in the entryway and canopies and aluminum metal panels were recycled.

To further stress the importance of material reuse, the building has its own recycling center: a collection point for paper, corrugated cardboard, glass, plastics, and metals.

The LEED certification program credits the use of local and regional materials because they require less fuel-consumptive transportation to get to the construction site. For the Front 5 Building, these included maple wood, gypsum board, structural steel, doors, paint, cabinetry, concrete, joists, rebar, insulation, brick, storefront windows, and concrete stain. Use of such materials also benefits the local economy.

Leading the City

At the site scale, the mere fact of renovation instead of new development aids in preserving urban density. In sharp contrast to a similar building in a suburban "industrial park," the Front 5 Building boasts six bus routes located within a quarter mile (400 meters). Bicycling is encouraged by the installation on an on-site bike parking rack and a shower/ changing room for employees.

To reduce site-scale heat build-up, the "urban heat island" effect, trees were planted on the south end of the parking lot and sidewalk to shade concrete and asphalt surfaces. A highly reflective, light-colored roofing material further reduces heat island effect and assists in reducing the building's cooling load.

Elsewhere on the site, the exterior lights were capped to reduce night sky light pollution. Water efficiency was ensured with a drip irrigation system and with a low-flow/ high-pressure plumbing system.

Indoor air quality has been ensured by use of materials — adhesives, sealants, paints, carpet, and composite wood — that are low in potentially irritating or harmful volatile organic compound (VOC) emissions. Moreover, the whole building has been designated a nonsmoking facility, with a permanent carbon dioxide monitoring system installed. These measures, along with a "green" housekeeping program, add up to a cleaner environment expected to improve occupant productivity.

"We wanted to design a space that would make a statement that sustainable design can be attractive, forward thinking, and most of all practical," says Stan Cole, principal of cole + poe architects. He expects that the project's somewhat above average construction costs will be offset over the building's life by savings in reduced maintenance costs, lower utility bills, and higher tenant occupancy rates.

The team further hopes the building will enhance local environmental awareness and set an example for future green urban redevelopment in the Boise community.

Front 5 has received recognition from Idaho Smart Growth, the Urban Land Institute, and the Idaho Business Review.   >>>

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SUBSCRIPTION SAMPLE Main entry of the Front 5 Building in Boise, Idaho renovated to LEED standards by cole + poe architects. Photo: cole +poe Newly punched clerestories contribute to substantial daylighting. Photo: cole +poe The warehouse before renovation. Photo: cole +poe Salvaged heavy timber was reused in the renovation. Photo: cole +poe Many factors contributed to the project's sustainability performance. Photo: cole +poe Front 5 Building site plan. Image: cole +poe Front 5 Building ground floor plan. Image: cole +poe Front 5 Building mezzanine. Photo: cole +poe   Click on thumbnail images to view full-size pictures.