Microclimate-driven spatial patterns for adaptive urban design: Evidence from Kotahena, Sri Lanka

Abstract

Rapid urbanisation and unplanned vertical expansion in tropical cities have intensified environmental pressures within dense informal neighbourhoods where urban form evolves beyond formal planning control. In many global cities, including those in Sri Lanka, everyday urban environments emerge through incremental development driven by economic constraints, with buildings predominantly constructed through labour-intensive and experience-based practices rather than professionally standardized construction processes. This ad-hoc development, combined with a growing population, has produced saturated built environments that intensify microclimate stress at street level. Interventions for such contexts typically rely on conventional sustainability frameworks that prioritise technical or climate-based solutions, while insufficiently engaging with the lived spatial and social dynamics of everyday urban environments. While climate-responsive urban research frequently evaluates environmental performance, fewer studies examine how microclimatic conditions shape spatial behaviour patterns that structure everyday urban life. This paper investigates the relationship between microclimate and spatial behaviour in dense informal contexts using Kotahena, Colombo. The study integrates spatial analysis, behavioural observation and microclimatic simulation to examine how urban morphology influences thermal comfort and patterns of urban activity. Comparative analysis reveals consistent relationships between thermal conditions and spatial behaviour patterns. The research proposes a framework for microclimate-driven spatial patterns capable of informing adaptive urban design strategies for this dense tropical environment. The patterns provide practically applicable guidance for policy and planning, supporting climate-responsive urban environments while remaining compatible with informal and experience-led urban development practices.