Division 13 Metro Bus Maintenance & Operations Facility

LEED Gold mechanical and building automation for a 200-bus Metro CNG maintenance facility — self-performed, design through commissioning.

Client: McCarthy Building Companies, Inc.
Location: Los Angeles, CA
Year: 2016
Service Line: Design-Bid-Build Mechanical

Division 13 is a 540,000-square-foot, $120 million bus maintenance and operations facility on the edge of downtown Los Angeles — Metro’s sixth LEED building, opened in 2016 to keep 200 compressed-natural-gas buses moving through Central LA. McCarthy was the general contractor. We came in as the mechanical HVAC and building automation subcontractor, our scope from drawings through final air balance.

The building was engineered to be efficient before our equipment ever switched on: heat-gain-reduction glazing, a cool roof and a planted green roof, shade structures and natural ventilation, daylight pulled into every major work area. Our job was to hold comfort and air quality across all of it, on a compact, stacked, urban site — a fueling hall, wash and chassis-wash bays, maintenance bays, and two levels of transportation offices, each with its own load.

A building full of compressed-natural-gas buses doesn’t forgive shortcuts on ventilation. We installed natural gas and carbon monoxide detection tied to variable-speed exhaust evacuation, building pressurization control, and maintenance-bay ventilation that ramps to the hazard, not the clock. The whole thing runs on a full direct digital control system with integrated energy management.

What we installed:

• High-efficiency condensing hot water boilers, 30:1 turndown, staged into smaller systems
• Two 300-ton centrifugal chillers and fourteen high-efficiency custom-built air handling units
• Chilled- and hot-water piping distribution with VSD pumps
• Supply and return duct distribution, duct sound attenuators, and CHW/HW/duct insulation
• Maintenance bay ventilation and Big Ass Fans
• Variable air volume system with raised-floor underfloor pressurization
• Enthalpy-based humidity control and demand ventilation
• Natural gas and carbon monoxide monitoring, with variable-speed exhaust evacuation
• Building pressurization control
• Full direct digital control system with integrated energy management
• Indoor and outdoor air quality monitoring and control
• System commissioning and final air balance

It all rolls up to LEED Gold under the U.S. Green Building Council: indoor air quality held through construction, high-efficiency equipment and demand-based ventilation cutting energy, local labor and materials, construction waste recycled. Check out some further facts on the Metro project fact sheet.

Ten years on, we’re still on the building. Athena services the building management system and the CO detection that keeps the bus bays safe, including the regulatory checks those systems have to clear. Metro is a current service customer, not a name in an old project file.

It isn’t the only Metro transit facility on our board. See the El Monte Busway & Transit Center.

Photo credit: McCarthy Construction & Metro. General Contractor: McCarthy Building Companies. Architect: RNL Design (now Stantec). Project fact sheet courtesy of Metro.