Mann Elementary Addition and Renovation
Iowa City, Iowa
A part of the Iowa City Community School District, Mann Elementary is a 100-year-old building that underwent modernization renovations and an addition to accommodate a new main entrance, media center, art room, music room, and gymnasium.
- Vertical, self-contained, water source high efficiency heat pumps with individual space control are utilized to provide space temperature control in each classroom. Support spaces use horizontal, water source high-efficiency heat pumps located above ceilings.
- A closed loop fluid cooler and high efficient condensing boilers provide heating and cooling for the heat pump system.
- Code-required outside air for the heat pump system is provided by three energy recovery units. The units include direct expansion cooling and hot gas reheat to dehumidify outdoor air and gas heating to prevent frosting on the energy recovery unit heat transfer surface during extremely cold ambient air temperatures.
- Lighting control systems were provided for interior lighting that incorporates vacancy sensors, occupancy sensors, manual dimming, multi-scene control, and automatic daylight harvesting where natural daylight is present. The interior lighting design proved to be 78% more efficient than the baseline code energy allowance and the exterior lighting design proved to be 91% more efficient.
- Exterior lighting is controlled through a programmable astronomical timeclock with multiple scheduled events allocated. Exterior parking lot lighting includes bi-level control, allowing the district to reduce parking lot luminaires to 50% when desired.
- Energy-saving strategies:
- Energy recovery unit zoning allows shut off when areas are unoccupied.
- CO2 demand control ventilation is utilized in the gymnasium and multipurpose rooms to save energy on ventilation cost. Specifying heat pumps with efficiencies above minimum code requirement.
- Energy efficient LED luminaires with soft diffusing optical lenses and reflectors throughout the building interior and exterior.
Photography credit: Wayne Johnson Main Street Studio