Lake Washington School District – Rachel Carson Elementary

Coffman provided electrical engineering for a new, 57,200 sf elementary school. A green roof covers two sections of the school and is the first green roof on a school building in a K-12 school district in the state of Washington. Natural ventilation is part of the building’s design. Windows in almost every classroom can be opened. Each classroom features a thermostat and a CO2 sensor with LED lights. The lights indicate when windows should be closed or left slightly cracked for minimum ventilation to allow the heating system to perform, windows can be opened or closed as desired because the outside temperature is mild, or when windows should be opened slightly. Exhaust ventilation dampers open and exhaust fans turn on automatically.
The lighting with square feet exceeds the Washington State Energy Code by 20% using “Super T8” lamp and ballast combination. No direct-beam illumination leaves the building site which reduces light pollution. Individual meters were installed for various plug loads to monitor electrical demand and consumption so the school can manage and optimize energy usage.


  • Education


  • Electrical Engineering