An infill development on the State of Iowa Capitol Complex, the Iowa Utilities Board - Office of the Consumer Advocate office building was developed on a 6 acre former landfill site, creating a gateway to the State Capitol complex at its Southeast corner. From inception, this office building was charged with meeting an energy use intensity goal of 28.0 kBTUs per square foot per year, equivalent to 63% energy savings beyond the energy Code baseline (ASHRAE 90.1 2004). All project decisions were measured against this goal. The building serves as a testament to the sustainable stewardship of the State of Iowa demonstrating proven, cost-effective new construction energy efficiency measures. Actual measured energy usage after the first 6 months of occupancy (including the typical hottest and coldest months of the year) indicate the goal was surpassed as the buildings energy use intensity is at a yearly average of 23.7 kBTUs (67.5% savings - without inclusion of on-site renewable energy). The IUB-OCA building is organized into two wings with an entrance / lobby link between: The north wing comprises the State Utilities Board on levels one and two while the south wing is comprised of the States Consumer Advocate Office on level two and common space on level one. Common space includes a hearing room, conference center and lounge space. A narrow building configuration in the north and south direction provides proper orientation for daylighting and natural ventilation opportunities. Daylight harvesting sunscreens at the south elevation of each wing supplement a holistic daylighting strategy while zinc clad office enclosures cantilever from the north elevations. This allows open office space to take advantage of the footprint depth to which Southern daylight can be delivered. Significant glazing at both the South and North elevations offers occupants views of the surrounding landscape in addition to daylighting throughout. Meanwhile, glazing at Western and Eastern elevations is limited to specific views so as to mitigate glare and heat gain provided by such exposure. White precast concrete with continuous insulation and non-thermally conductive ties offers a simple yet high performance skin, eliminating traditional thermal bridging at roof interfaces, foundation walls and wall openings. After loads were reduced through envelope means, a geothermal system delivers significant energy savings. On-site renewable energy generated through roof top photo voltaic panels further reduce consumption by approximately 14.5% but were considered only after all of the free energy through efficiency measures and load reduction were captured. Additional mechanical strategies include a total energy recovery ventilator, premium efficiency heat pumps, perimeter radiant heating and demand controlled ventilation. Electrical strategies incorporate occupancy sensor control of lighting and non-critical plug loads throughout. Lighting power density was reduced to 0.55 watts per square foot. A simple strategy of no site irrigation, ultra low flow plumbing fixtures and faucet aerators allows for domestic water savings exceeding 46% below the code baseline. Site features include a storm water treatment train to capture and infiltrate site storm water as well as an additional diverted 6 acres of off-site stormwater. The southern portion of the site is comprised of a native prairie restoration featuring the final infiltration basins of the stormwater treatment train. Native vegetation throughout provides wildlife habitat and eliminates all irrigation. The project is on track to achieve LEED Platinum Certification and expects to receive certification soon.