Seattle Department of Transportation (SDOT) recently completed the First Hill Streetcar line, a 2.5 mile, $135M project designed to support economic growth and strengthen connections between Capitol Hill, First Hill, and the Chinatown / International District. Waterleaf Architecture teamed with LTK Engineering to design the 20,000 square foot Operations and Maintenance Facility serving the needs of the new line. Efficiency, initial and long-term costs, safety, and energy efficiency were primary considerations informing the design of the facility.

The First Hill O&M Facility, which achieved LEED Gold certification, features a significant reduction in energy usage compared to similar facilities. Sustainable building features include a full vegetated green roof for stormwater collection, pervious paving to maximize stormwater infiltration and reduce heat island effect, a 6.3 KW photovoltaic array, radiant in-floor heating, energy efficient variable refrigerant flow (VRF) system, and passive ventilation.
interior diagram of the sustainability features in the facility


 1    Full vegetated (Green Roof) to maximize stormwater retention and mitigate heat island effect
    Pervious concrete pavers to maximize stormwater infiltration and reduce heat sland effect
 3    Bioretention area for roof stormwater collection
 4    Outdoor patio
    Renewable energy 6.3 KW photovoltaic array
 6    Radiant in-floor heating
 7    High efficiency LED and fluorescent interior and exterior lighting with lighting timers and occupancy / daylighting sensors.
 8    Abundant daylighting (north clerestory, east & west translucent wall system and skylights)
 9    Passive ventilation of the maintenance shop utilizing stack ventilation
10    Operable windows and skylights provide natural ventilation and cooling
11    No irrigation system installed – i.e. no potable water use for irrigation (because of native and adaptive species used)
12    Third party certified lumber (FSC – Forest Stewardship Council), ensuring responsible management of forests  


+  Electric car charging station
+  Bicycle storage and showers
+  Energy efficient Variable Refrigerant Flow (VRF) system
+  Energy recovery ventilator
+  High efficiency DHW heater
+  High efficiency hydronic heating boiler
+  Heat reclaim from electrical room
+  High recycled content, low VOC and regionally produced materials.
+  Efficient plumbing fixtures for more than 35% potable water use savings.
Interior of the First Hill Streetcar facility. Large windows flank the building bringing in day light.