American Institute of Certified Planners (AICP) Practice Exam

What is density in land use planning typically measured in?

1. Dwelling units per square kilometer

2. Dwelling units per square mile

3. Dwelling units per acre

4. Dwelling units per hectare

The correct answer is: Dwelling units per acre

In land use planning, density is a critical concept that reflects the number of residential units or dwelling spaces within a defined area. Measuring density in dwelling units per acre is commonly used in the United States and allows planners to understand how populated a specific area is, which influences decisions related to infrastructure, public services, and environmental impact. Using dwelling units per acre provides a granular view of how land is utilized, particularly in suburban and urban settings where land use efficiency is a significant factor. This measurement helps in zoning decisions, determining the required services (like schools and parks), and assessing the suitability of an area for new development. While other units of measurement like square kilometers, square miles, and hectares are indeed valid, they tend to be less prevalent in American planning contexts and can complicate understanding for local stakeholders who may be more familiar with the acre as a measurement standard. Therefore, dwelling units per acre is a standard metric for assessing density in many U.S. planning scenarios, making it the most appropriate and commonly recognized answer for this question.