The Open Space Ratio (OSR) is a quantitative measure used to assess the proportion of open spaces within a given urban area. It is typically expressed as the ratio of open space to the total area of a development or a city. To illustrate, if a building encompasses 20,000 square feet of floor area and has an OSR of 20, it would necessitate 4,000 square feet of open space on the zoning lot (0.20 × 20,000 sq ft). (nyc.gov, 2023)
The open spaces include parks, gardens, green belts, plazas, waterfronts, and other recreational areas. Benefits of a High OSR are enhancing physical and mental wellbeing, environmental sustainability, social cohesion and community building, as well as economic benefits, as well-designed open spaces can significantly increase property values, attract businesses, and drive tourism. They create opportunities for small businesses and local economies, promoting economic growth and enhancing the overall attractiveness of the urban area. (cdc.gov, 2020)
OSR in Urban Planning sets benchmarks for urban development. Establishing minimum OSR requirements in urban planning regulations ensures that developers allocate sufficient open spaces. This helps create a balance between built-up areas and green spaces, preventing overcrowding and maintaining a healthy urban environment.
OSR also plays a crucial role in ensuring equitable access to open spaces for all residents, regardless of socio-economic background. Planning policies that mandate OSR take into account factors such as population density and proximity to open spaces, ensuring that communities have fair and adequate access to recreational areas.
By integrating OSR into urban planning, cities can promote sustainability and resilience. Open spaces can be designed to incorporate green infrastructure, such as rain gardens and urban forests, facilitating water management, reducing energy consumption, and promoting ecological balance. A higher OSR contributes to healthier communities by providing opportunities for physical activity, reducing sedentary lifestyles, and improving air quality. Accessible open spaces promote active living and contribute to the prevention of chronic diseases, such as obesity and cardiovascular conditions.
