Analytical Investigation of Fire-Resistant Material Performance in Nigerian Residential Construction

Fire safety in Nigerian residential buildings is inadequately addressed by both construction practice and planning regulation, with the prevalent material combinations in common use untested under fire-resistance rating standards relevant to the Nigerian construction context. This study analytically investigates the fire-resistant performance of building material combinations typical of Nigerian residential construction, combining experimental furnace testing with a field survey of construction practices across residential buildings in three geopolitical zones. Standard fire-resistance tests were conducted on twelve wall assembly configurations representing combinations of sandcrete block, clay brick, stabilised compressed earth block, and varying plaster finishes, following ISO 834-1 standard time-temperature curve procedures at the Lagos State University Materials Testing Laboratory. Each assembly was rated for fire resistance period in minutes, failure mode, and post-fire structural integrity. Field surveys of residential construction practice in Onitsha, Abuja, and Kano documented the prevalence of tested material combinations in residential contexts and identified fire-hazard adjacencies including kitchen configurations and electrical distribution arrangements. Results show that 225 mm sandcrete block walls with lime plaster finish achieved the highest fire resistance rating at 95 minutes, while 150 mm block walls without plaster fell below the 60-minute minimum recommended for party walls. Compressed earth block assemblies outperformed sandcrete of equivalent thickness by an average of eighteen minutes. The absence of fire-resistant ceiling boards between roof spaces and occupied volumes in the majority of surveyed Nigerian homes is identified as a critical fire spread pathway. Recommendations address material specification standards in the Nigerian Building Code review. Keywords: fire-resistant materials, residential construction, fire safety, building materials testing, Nigeria.