Evaluating the Energy Efficiency of Green Roof Systems in Residential Buildings: A Case Study in Abuja, Nigeria

This study assesses the impact of green roof systems on electricity consumption in a residential building located in Abuja, Nigeria. Using empirical data from the Abuja Electricity Distribution Company (AEDC) in an existing building for instrument validation and simulation outputs from EnergyPlus via DesignBuilder, the research compares three roof scenarios: conventional, intensive green roof, and extensive green roof. Results reveal that buildings with extensive green roofs consistently exhibit the lowest monthly electricity demand, averaging below 700 kWh, while conventional roofs peak at over 940 kWh. A Pearson correlation coefficient of 1.000 between actual and simulated data confirms the reliability of the simulation model. The findings emphasise the energy-saving potential of green roofs, particularly extensive systems, in hot-humid climates and support their integration into sustainable building design strategies