Math & Engineering
Floor Area Ratio (FAR) Calculator
Calculate the Floor Area Ratio (FAR) to determine building density and land use efficiency
Enter values to calculate the Floor Area Ratio
Related to Floor Area Ratio (FAR) Calculator
The Floor Area Ratio (FAR) calculator is a fundamental tool in urban planning and real estate development that helps determine the density and intensity of land use. It calculates the relationship between a building's total floor area and the size of the lot it's built on. The calculation is straightforward: FAR is obtained by dividing the total floor area of the building by the total area of the lot.
The Formula
Floor Area Ratio (FAR) = Total Floor Area ÷ Lot Area
For example, if you have a building with a total floor area of 20,000 square feet on a lot that's 10,000 square feet, the FAR would be 2.0. This means the building's total floor area is twice the size of the lot. The calculator supports both square feet and square meters, allowing for flexibility in unit selection while maintaining accurate calculations.
Understanding your FAR result is crucial for urban planning and development decisions. The FAR value provides insights into building density and land use efficiency. Here's how to interpret different FAR values:
Common FAR Values
- FAR < 1.0: Building's floor area is less than the lot size (low-density development)
- FAR = 1.0: Building's floor area equals the lot size
- FAR > 1.0: Building's floor area exceeds the lot size (high-density development)
- FAR 2.0-5.0: Typical for urban commercial districts
- FAR > 5.0: Common in dense city centers with high-rise buildings
The FAR result helps planners, developers, and architects determine if a proposed building complies with local zoning regulations and whether it makes efficient use of the available land. Higher FARs generally indicate more intensive land use and are often found in urban centers, while lower FARs are typical in suburban or residential areas.
1. What is included in the total floor area calculation?
Total floor area typically includes all usable space within a building, including all stories above ground level. This usually encompasses interior floor space, but may exclude mechanical rooms, stairwells, elevator shafts, and parking areas, depending on local regulations.
2. Why is FAR important in urban planning?
FAR is a crucial zoning tool that helps control building density and urban development. It ensures consistent development patterns, manages population density, controls traffic impact, and helps maintain the desired character of neighborhoods while making efficient use of available land.
3. Can FAR requirements vary by location?
Yes, FAR requirements often vary significantly by location, zoning district, and land use type. Urban areas typically allow higher FARs to encourage density, while suburban or residential zones may have lower FAR limits to maintain a less intensive development pattern.
4. How can I increase my building's FAR?
FAR can be increased by adding more floors to a building, maximizing the buildable area on each floor, or through zoning bonuses that may be available in your jurisdiction. Some areas offer FAR bonuses for including certain amenities or meeting specific design criteria.
5. What is the scientific source for this calculator?
The Floor Area Ratio calculation is based on standardized urban planning principles and architectural measurement standards established by organizations such as the American Planning Association (APA) and the International Code Council (ICC). The formula and methodology follow the guidelines outlined in the APA's Planning Advisory Service (PAS) reports and the ICC's International Building Code (IBC), which are widely accepted standards in urban planning and development. The calculation method is also consistent with academic research in urban planning, particularly in studies of building density and land use efficiency published in the Journal of Urban Planning and Development.