Loyola Elementary School is an existing public school in Los Altos, California. “The project demonstrates that performance and amenities matching that of new buildings can be cost effectively achieved in a modernization, observing the first choice of sustainability – to reuse what already exists,” states project architect Lisa Gelfand, Gelfand Partners Architects. The existing facility was a finger plan suburban school built in 1948. The team considered demolishing the school as an alternative to modernization but concluded that the favorable solar orientation and the generally sound structural framing and foundations argued for reuse. The project gained Savings By Design and state energy efficiency grants for the district, beating Title 24 by 35% using a combination of envelope improvements, increased daylight, daylight compensation lighting controls, and innovative HVAC. The school and district administration were involved in determination of appropriate lighting levels and decisions to optimize fresh air as part of the HVAC system, and to use the district EMS system to control motorized window openings.
Part of a high performance master plan for the entire district, the school uses daylighting, natural ventilation, green materials, and adaptive reuse of existing structures both for their intrinsic benefits and to model for kids an attitude of responsibility and ongoing economy. Part of the seismic improvements to the school called for filling in shear panels at existing wall-to-wall north glazing in the classrooms. To rebalance the lighting for the classrooms the team added new roof monitors with clerestory windows that function both to bring in additional daylight and as part of the stack ventilation system. Project display windows within the shear walls restore raking light to the walls between classrooms while supporting the project oriented curriculum of the school. Clerestories are placed immediately adjacent to the ceiling in order to maximize reflected daylight. Continuously dimming compensatory lighting controls maintain even ambient lighting as daylight fluctuates, rarely running at more than 10% of capacity. Occupancy sensors limit energy use by lighting or HVAC when rooms are not in use. Door interlocks shut off air-conditioning when doors are open, prompting kids to remark that the buildings are “smart.”
All electric heat pump HVAC units are supplemented by automatic operation of clerestory windows. The EMS system signals a motor to open the windows when air temperatures are appropriate. The stack effect then draws fresh air in from louvers low on the outside walls. This innovative system replaces the fans of economizer cycles on HVAC equipment with a single action of opening the window. The resulting air velocity and pressure is strong enough that filters are required at the louvers to prevent dust and dirt from being drawn into the classroom from the outside. Existing windows are reused and new windows installed with standard, easily replaced single glazing while walls and roof/ceilings in both new and modernized buildings have R-21 and R-30 insulation. The tackable wall finish is a green linoleum material. |
