Low Energy Building Design for the 2020 DOE Solar Decathlon: Retr[OLPH]it
Elementary School Category

The retrofit of the Our Lady of Perpetual Help Elementary School was performed as part of the Solar Decathlon 2020. This project aimed at improving the energy performance, indoor environment quality, usability, and overall sustainability of the school. Members of the project team analyzed all existing building systems and designed alternatives to achieve the overall goals of the Solar Decathlon. The final design features of the building envelope include a drastically reduce air leakage rate, roof RSI value of 12.33 m2K/W, wall RSI value of 5.28 m2K/W, foundation RSI value of 5.99 m2K/W, and window U-value of 0.97 W/m2K. In addition, the mechanical and electrical systems of the building were replaced with energy efficient Air-Source Heat Pumps for space conditioning, Dedicated Outdoor Air Systems for ventilation and LED lights for lighting.
These improved mechanical and electrical systems were also complimented with a 232 kW solar array, installed on the roof of the school and on the added canopy above the existing parking lot, capable of producing over 253 MWh of solar energy per year. The environmental impact of the retrofit was reduced by using mass timber for the majority of the structural additions, including the new gymnasium. Battery storage, window sizes for optimal daylighting and water efficient fixtures are some of the additional strategies implemented in this retrofit. All of the implemented designs and strategies were modelled in various software to assess the energy performance of the building and the percentage improvements over the existing building to provide any potential stakeholders with quantitative data showing the benefits of the design.