Policy Awareness and Preferences for Passive Climate-Responsive Retrofitting in the Residential Building Sector: Evidence from Lagos, Nigeria

Residential buildings in tropical regions contribute significantly to extreme indoor heat, low air quality, and excessive cooling energy demand, yet the widespread adoption of passive climate‑responsive retrofit measures remains limited. In Nigeria, it is not clear to what extent there is an awareness of such policies, nor is it clear to what extent different passive retrofit measures are well understood and preferred. This study examined policy awareness and preference for passive retrofit measures by using quantitative data from 118 property managers and 163 homeowners in Lagos State, Nigeria, and semi-structured interviews of officials from the various building regulatory and control agencies. From the results of the Mann-Whitney U-test, there was no significant awareness of a national environmental policy (NCCP; p-value > 0.05), although there was a significant lack of awareness of policies on building efficiency (BEEC, BEEG, and EDGE; p-value < 0.001). The emphasis on passive retrofits is evident in the mean scores of 4.45 for “planting trees and vegetation around buildings to provide natural shade and reduce cooling loads”, 4.38 for “enhancing the building's ability to prevent moisture from entering or escaping”, and 4.24 for “integrating openings in building envelopes”, thus establishing that these are the most preferred solutions. However, from the fuzzy TOPSIS analysis, the highest value of CCᵢ was 0.974 for “enhancing the building's ability to prevent moisture from entering or escaping” and the lowest value of 0.000 for “increasing the thickness of wall insulation layers to reduce heat absorption.” Based on these findings, technical retrofit solutions are less preferred than nature-inspired and easy solutions. The qualitative study revealed that passive retrofits are embedded in the national building code, rather than being included as a retrofit policy. It is therefore necessary to first identify solutions and programs that resonate well with property managers and owners, using this as the foundation to slowly build up to more technical solutions.