How is the footprint of a building determined?

There are several variables to balance here:

Gross Area

  • The program area (assignable net square footage) such as an executives office.
  • General Circulation (shared square footage) such as hallways.
  • Other non assignable square footage but necessary to a building's operations like mechanical and equipment areas.

Number of Floors

  • Program may require several floors.
  • Zoning Requirements - May limit the number of floors or set backs which could change the base footprint.

FAR

  • The floor area ratio balance changes the base footprint. The FAR controls how large a building can be based on the size of the property.

Building Configuration

  • First floor, mezzanine, equipment, penthouse, and rooftop floors will differ from the others.

Site

  • Unique site factors such as a dramatic slope, marshland, or toxic soil may change a building's footprint.
  • For a site in the Northern Hemisphere an orientation between 5 and 25 degrees east of south best achieves the balance of summer and winter heat gains.
  • Site access may dictate entry and exit locations as well as deliveries.
  • Topography and micro climate are important factors like winds, location of trees, and distance to water.
  • Views are often a concern in areas such as the Hollywood Hills or in Santa Barbara
  • Utilities and Infrastructure
  • Sun Angle
  • Climate (Macro and Micro-climate)

Cost and Value

  • The higher the perimeter to floor area ratio; the greater the unit cost.
  • The greater the floor area; the lower the unit cost.
  • Maximizing square footage of a lot may be a priority of the client. This is common in highly competitive markets.

Design

  • Earth berm shelter - creates energy savings
  • Waterfront Views - Value of land may necessitate its use
  • Podium for parking (Theaters) or commercial business (mixed use)
  • Iconic forms such as the Ordos Museum have a unique footprint.