Environmental Impact Assessment (EIA) is widely recognised as a key instrument for integrating environmental considerations into development planning. However, its effectiveness within the built environment is often constrained when implementation emphasises procedural compliance over multidisciplinary knowledge integration. Consequently, environmentally significant development-performance variables may receive insufficient attention despite their implications for sustainability outcomes. This paper develops a multidisciplinary framework for strengthening Environmental Impact Assessment within warm-humid climatic contexts. The study adopts a conceptual-review approach supported by an illustrative thermal-performance case study from Owerri, Nigeria. Literature was synthesised from Environmental Impact Assessment, environmental management, building physics, sustainable development, urban climatology and climate-responsive design. The Owerri case utilised 1,602 paired attic–indoor temperature observations to dem