BRIDGING THE HOUSING DEFICIT IN NIGERIA: ENERGY AND CO2 EMISSIONS IMPLICATIONS

Affordable and decent housing constitute an important component of the urban infrastructure of any nation. In Nigeria, the housing deficit was estimated in the year 2012 to be about 17 million. Understandably, the huge financial and complex logistical implications of bridging the deficit appear to have dominated academic discussions on the subject matter. This paper attempts to address the energy and CO2 emission implications of mitigating the huge housing deficit. Using a predominant urban social housing typology in the highly urbanized city of Lagos as a basis, the paper estimated the embodied energy and CO2 emissions associated with providing the additional housing units needed to bridge the deficit. The life cycle energy analysis framework was adopted for the study with the Inventory of Carbon and Energy (ICE) as the main source of embodied energy and CO2 coefficients. It was found that given a housing unit footprint of 120m2 and a building life span of 50 years, the embodied energy and CO2 emissions intensities for the prototype were 7378MJ/m2 and 589kg/m2 respectively. For the additional housing units, the above intensities translated to about 15.x 1012 MJ of embodied energy and 1.2 x 1012kg of CO2. With respect to the building components, the largest contributors to the embodied energy and carbon profile were the substructure, frame and upper floors as well as internal and external walls and the key materials for the components were cement and steel reinforcement. In order to reduce the estimated embodied energy and carbon impact of providing the additional housing needs, the targets for mitigation should be the concrete, steel reinforcement and envelope/partition materials of the building