5a. What is density?

Density is often misunderstood. Density in the context of urban planning and design has a number of different definitions and considerations, including residential density, site density and site coverage.

Well designed, compact infill in cities and communities is fundamental to “smart growth.” Smart growth is an approach to development that encourages a mix of building types and uses, diverse housing and transportation options, development within existing neighborhoods, and community engagement. It contains 10 principles including: creating a range of housing opportunities and choices; taking advantage of compact design, and; making development decisions predictable, fair and cost effective.

Planning addresses the use of land, resources, facilities and services in ways that secure the physical, economic and social efficiency, and the health and well-being of urban and rural communities.

Urban design considers the arrangement of buildings, streets and public spaces, neighborhoods and districts, with the aim of making these areas functional, attractive, and sustainable. It plays an important role in maintaining and enhancing the quality of life in Canadian cities. High-quality urban design comes from the expertise of planners, architects and landscape architects.

Residential density typically refers to the number of people inhabiting a given urbanized area. For example, the number of people residing or working in a particular area, such as 95 people per square hectare.

Site density typically refers to the total floor area of all buildings on a lot divided by the lot area.  It is commonly measured using “floor space ratio” (FSR) — in other words, the  ratio of floor area to land area.

Site coverage typically refers to the footprint that all buildings and structures make on a site (e.g. the area occupied by the building or proportion of land covered by buildings). A building may be very tall with a small footprint (high-rise low coverage) or a building may be only one storey but cover the entire site area (low-rise high coverage).