Ten Questions Concerning the Environmental Impacts of Housing Built Form
Housing aims to provide society with comfortable, healthy living spaces and its built form ultimately shapes the built environment. Consequently, its design, operation, and interactions with infrastructure systems are a powerful determinant of environmental, economic, and social impacts.
This paper highlights the importance of assessing housing built forms by answering ten critical research questions. Throughout this paper, we refer to housing built form as the physical properties (e.g., residential density, floor area ratio) of residential buildings and their interactions with adjoining properties (e.g., setback, shading). In Q1 and Q2, we summarize the planning policies that led to current built forms associated with housing and their sustainability impacts, with specific focus on North America and some countries in Australasia. Q3 describes the adverse sustainability impacts of detached single-family houses, while Q4 examines future economic, demographic, and climatic changes that will warrant rethinking housing built form. Q5 summarizes the methods to assess the environmental, economic, and social impacts of housing built form. In Q6 and Q7, we discuss various system boundaries and functional units that are considered for housing life cycle assessment. Q8 and Q9 describe the temporal uncertainty and contextual circumstances underlying housing projects that need to be considered in life cycle assessments. Lastly, Q10 provides a summary of future policy directions to promote housing with lower environmental impact. This paper supports decision-making around meeting housing targets without compromising the environment.