- Achieving Sustainable Site Design through Low Impact Development Practices
- Designing Buildings to Resist Explosive Threats
- Low Impact Development Technologies
- Psychosocial Value of Space
- Sun Control and Shading Devices
- Sustainable O&M Practices
- Threat/Vulnerability Assessments and Risk Analysis
- Water Conservation
Last updated: 07-22-2010
A public plaza is a community amenity that serves a variety of users including building tenants and visitors and members of the public. This space type may function as pedestrian site arrival points, homes for public art, settings for recreation and relaxation, and inconspicuous security features for high profile buildings. Plazas are a beneficial feature of any lively streetscape.
Programmatically, plazas are strongly linked to the lobby space type. Both are a "public face" for a building that welcomes and orients visitors.
The most important consideration in designing exterior plazas and public spaces is the future, potential use of those spaces. Plazas should be designed to cater to a diverse set of activities including those that are active or passive, formal or informal, group or individually oriented, and planned or spontaneous. Plazas should invite users to partake in programmed activities (eg. by providing seating, tables, and shade: lunchtime diners may be encouraged to frequent a space), but should also be flexible enough to accommodate activities that users plan themselves (a shaded, grassy area could host a performance, an impromptu game of Frisbee, or solitary reading). Typical features of plaza space types include the list of applicable design objectives as outlined below. For a complete list and definitions of the design objectives within the context of whole building design, click on the titles below.
- Access to Features: The design team must ensure that landscaping, level changes, or other architectural barriers do not prevent users from accessing amenities within a public plaza. This includes access to public art, water features, seating, and other fixed "furniture", like water fountains. See also WBDG Accessible—Provide Equal Access.
- Accessible Route: Grass and earth covered plazas must be well maintained in order to ensure compliant routes and ground surfaces. However, masonry surfaces can be easily designed with compliant slopes that meet accessibility standards and properly direct rainwater. In addition masonry surfaces are less expensive to maintain. See also WBDG Sustainable—Optimize Operational and Maintenance Practices.
- Materials: Utilize appropriate materials, furniture, signage, and art to reflect the public nature of the space. See also WBDG Materials.
- Water Features: Water may be used as a visual and acoustic element. However, water features should not become a maintenance burden. In colder climates provisions must be made for easy shut-off and drainage during the winter season. The U.S. General Services Administration restricts fountains and reflecting pools with pumping systems to Category I areas of a site. Water features should not be placed over occupied space since leakage problems occur frequently. See also WBDG Sustainable—Protect and Conserve Water.
- Sculpture: In and around federal buildings, sculpture may be provided as part of the GSA's Art in Architecture Program. Under this program, art is not addresses by the site designer except as a coordination effort since the sculptor is selected under a separate contract. However, it is crucial in such cases for the artist and the A/E to coordinate not only the art installation, but how people will move to and from each other's designed areas and how one might support the other.
- Cost-Effective Maintenance: It is important to ensure that routine maintenance of landscape elements, water features, and artwork in plazas can be performed at a reasonable cost.
- Use Durable Materials: Materials for outdoor amenities and furniture should be very durable and resistant to the elements and vandalism. Metals that do not require repainting are recommended.
- Encourage Flexibility: Plazas should be designed with electrical outlets lighting, and other simple infrastructure, to support future flexibility and encourage a wide range of uses. See also WBDG Functional/Operational—Ensure Appropriate Product/Systems Integration.
- Outdoor Furniture: Seating, tables, bollards, bicycle racks, cigarette urns, trash receptacles, flagpoles, lighting standards, and tree grates should be considered as part of the initial site design. Site furniture should be compatible in size, design, and color with the surrounding architecture and landscape design. Outdoor furniture is an essential element in creating useful and functional outdoor space.
- Seating: Seating is a public amenity that is appropriate to locate in the plaza areas of many federal buildings. Moveable seating can be an important component in effective public plazas. In many intensively-used public spaces, it is an effective supplement to built-in seating. Where appropriate, perimeter walls and stair elements should be designed to provide comfortable height and depth for seating. Seating should be designed and placed on the site to provide choices for employees and visitors. In addition, consider locating trash containers near seating areas and congregating points to encourage their use.
- Maintenance: The long-term upkeep and maintenance of landscape elements, lighting, fountains, and similar elements found in plazas must be considered during design. Equipment required for maintenance should be readily available, including such standard equipment as forklifts or electrical lifts.
- Programming Plazas: Consideration should be given to development of plazas and courtyards for employee and visitor uses, and for both planned and passive activities. It may also be possible to incorporate the building's program requirements into these spaces, for example, for use as outdoor dining or meeting spaces.
- Meet the Needs of Building Occupants: Well-designed plazas provide workers/occupants with a relief opportunity—such as breaks—from more confined spaces. See also WBDG Psychosocial Value of Space.
- Encourage a Variety of Activities: The design team should discuss with potential users how they would like to use the space, in order to incorporate appropriate amenities, relate outdoor areas to inside uses, accommodate traffic to and from the building, and provide for regular programmed use of the spaces and special events, as appropriate. Consideration should be given to different areas of a public plaza which would be appropriate for different types and intensities of public activities. With proper accommodations a plaza can bring the public in by housing performing arts events and vendors. See also WBDG Functional/Operational—Account for Functional Needs.
- Bollards and Landscape Elements: To prevent vehicles from accidentally or intentionally entering a plaza from adjacent public streets, it is recommended that barriers be installed along the border of the plaza. These barriers can be simple bollards or fixed landscape elements. Stairs, statues, water features, or large planters can be enjoyable for plaza users and aesthetically pleasing while providing security for the building and its occupants. See also WBDG Blast Safety of the Building Envelope.
- Manholes: The placement of manholes in plazas and entry courts should be avoided, particularly along the main pedestrian routes and walkways.
- Site Planning: Entrance plazas should have slopes of 1 percent minimum and 5 percent maximum to allow for proper rainwater run-off. In areas with snowfall, provisions should be made for piling snow removed from roads or adjacent parking and drop off areas. See also WBDG Sustainable—Optimize Site Potential.
- Storm Water Management: Where paved areas are adjacent to buildings, provide slopes of 2 percent minimum away from the structure to a curb line, inlet, or drainage way to provide positive drainage of surface water. See also WBDG Low Impact Development Technologies.
- Water Conservation: Water consumption should be kept low, especially in very dry climates with high evaporation rates. Non-potable water sources may be considered for water features and landscape maintenance. See also WBDG Sustainable—Protect and Conserve Water.
- Bicycle Racks: The U.S. Green Building Council suggests providing bicycle racks for approximately 5% of building occupants as part of their LEED criteria. Bicycle racks can be placed in plazas, near building entries. This location should be highly visible by building occupants, security personnel, or by general traffic. Racks should have provisions for using bicycle locks and should be compatible with building and site design. Providing a secure and convenient place to store bicycles encourages their use.
Relevant Codes and Standards
The following agencies and organizations have developed codes and standards affecting the design of Plazas. Note that the codes and standards are minimum requirements. Architects, engineers, and consultants should consider exceeding the applicable requirements whenever possible.
- GSA Commissioning Art in Architecture
- GSA Facilities Standards for the Public Buildings Service, P100
- International Building Code
Accessible—Provide Equal Access, Aesthetics—Understanding the Language and Elements of Design, Functional / Operational—Account for Functional Needs, Functional / Operational—Ensure Appropriate Product/Systems Integration, Productive—Provide Comfortable Environments, Secure / Safe—Ensure Occupant Safety and Health, Sustainable—Optimize Site Potential, Sustainable—Protect and Conserve Water, Sustainable—Optimize Operational and Maintenance Practices