Description of sustainable goals and features incorporated into this project

Sustainability has been a San José City Hall program goal since conceptual design began in early 1999. Since that time, the City has embarked upon an effort to implement a Green Building Policy based on the U.S. Green Building Council's whole building rating system, Leadership in Energy and Environmental Design (LEED).

LEED establishes four levels of green building certification, each based on cumulative points earned through design conformance to published LEED sustainability criteria. Formal LEED certification requires an application, documentation and verification process initiated at the start of design.

Although City Hall design began well before the City's policy development effort, the project goal is to incorporate as many green building features as feasible for maximize sustainability:

• High-performance exterior glazing to meet or exceed more restrictive state energy code requirements that went into effect June, 2001.
• A combination of exterior and interior shading devices that exclude solar heat and reduce cooling energy consumption.
• Light building color that absorbs less summer sun, reducing cooling energy demand.
• Day lighting of interior spaces to minimize artificial lighting demand, with photocell control.
• High-efficiency equipment and motors throughout to minimize operating demand.
• Programmable building automation system to allow optimizing systems and equipment operation in response to building occupancy and use patterns.
• Toilet and equipment make-up supply water plumbing will be configured for future conversion to Reclaimed Water.
• Alternatives for introducing natural ventilation sustainability are under study, to reduce daily/seasonal mechanical cooling energy.

The New City Hall also includes other sustainable design features that are included in the Sustainable Design Package for the project as a whole:

Sustainable Design Package

Transportation
Multiple modes of arrival at building, provision of bike racks
Provide electric car re-chargers
Promote car-pooling and use of public transportation

Materials
Low emissions, in particular, volatile organic compounds (VOC's)
Resource manufacturers of recycled materials to save energy and cost

Color
Light interior colors create feeling of higher light levels reducing need for artificial light sources
Light exterior colors increase reflectance, lowering heat gain

Energy
High performance glazing (exceeds T-24)
Orientation along east-west axis minimizes solar gain
Sunshading on glazing
High insulation facade (exceeds T-24)
Detailing, weather stripping and sealing of the envelope to prevent convective losses

Lighting
Rely on task lighting in lieu of lighting areas to level required for working

Landscaping
Use water-efficient irrigation systems
Landscape design minimizes run-off, maximizes rainwater penetration (if no underground parking)
Use plants to mitigate climate conditions (shade, windbreaks, etc.)

Construction
Demolition waste recycling
Require contractor to instigate recycling and utilize environmentally sensitive techniques
Strive for 'paperless' design in construction (electronic filing)

Garage
Carbon monoxide control system, if underground

System
Utilize variable air volume (VAV) air systems in offices
Utilize displacement ventilation in high volume spaces
Building Energy Management Control System (BEMCS)

Air Quality
High quality filtration (ASRAE standards 90-95%)
Pre-occupancy building purge-run systems at full exhaust to exhaust off-gassing pollution prior to occupancy

Refrigerants
Use low ODP and GWP refrigerants in chillers

Pollutants
Low NOX producing boilers

Water
Low water use toilets

Recycling
Provide space to facilitate recycling programs, office and cafeteria waste

Commissioning
Require commissioning of building prior to opening, make sure all systems are operating together and as designed (this is different than "test and balance").

Maintenance
Provide maintenance space in equipment rooms; BEMCS includes maintenance software; ensure that equipment performs at highest efficiency, minimizes replacement and downtime.

Enhanced Sustainable Design Features

Day lighting
Atriums and day lighting sunshades maximize daylight penetration and occupant connection with exterior
Integrate daylight with other building systems and strategies

Mechanical System
Augment air distribution with natural ventilation system (operable windows)

Gray Water System
Separate gray water system for non-potable purposes

Systems Distribution
Under floor air distribution system