Westside School

Seattle, Washington

Leveraging the old to create a new high-performance space for students and their teachers

The Westside School in West Seattle showcases the power of adaptive reuse, transforming a 35,000 SF 1970s-era church into a highly energy-efficient 55,000 SF K-8 school. With a measured Energy Use Intensity (EUI) of 14.3 kBTU/ft²/yr—one of the lowest for a non-PV school in the Northwest—this project demonstrates how innovative mechanical design can drive sustainability while preserving architectural character.

To achieve exceptional energy performance, the mechanical system was designed for efficiency, flexibility, and cost-effectiveness. The building utilizes a Variable Refrigerant Flow (VRF) system for zonal heating and cooling, ensuring precise temperature control while reducing operating costs. Dedicated outside air systems (DOAS) with energy recovery ventilation (ERV) provide fresh air efficiently, responding dynamically to occupancy and indoor air quality demands. Unlike traditional large central HVAC systems, this decentralized approach minimizes energy waste by conditioning spaces only when needed.
Smaller ERVs and ducts optimize ceiling space while reducing system complexity and cost. The variable-capacity heat pump control system integrates occupancy sensors within thermostats, automatically setting back heating and cooling when spaces are unoccupied. The controls are also synchronized with the DOAS units, further streamlining operation and energy savings.

By embedding the existing structure within a high-performance thermal envelope and implementing a right-sized mechanical strategy, Westside School achieves a 70% energy reduction compared to typical Seattle schools.

Learn more about this project here:

• From Church to School. ASHRAE High Performing Buildings Magazine, Winter 2017.