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Purpose The purpose of this paper is to investigate the extent to which green building features are evident in office properties in Lagos, Nigeria; and consequently determine the degree of compliance with green standards in the country. Design/methodology/approach The study purposively sampled two (2) office properties from the management portfolio of 88 registered Estate firms in Lagos. Data were collected using physical observation on the properties and interview with two users purposively selected from each of the properties. The data were analysed with the use of frequency distribution, percentages and measures of green features availability index. Findings The result revealed a low extent of green features incorporation in existing office properties with the value of availability indices on most features falling below 2.5 on a five-point scale. Feature relating to material use and conservation is the most incorporated green feature (mean score of 2.62) while those relating to owner and occupant education were least in incorporation (mean score of 1.895). Practical implications From the findings, it is apparent that green retrofitting may be necessary in Nigeria due to the low extent of green practices in existing office properties. Also, reinforcement of existing government policies and increased sensitisation of stakeholders on impact of current building practices are pertinent to green building success in Nigeria. Originality/value Most existing studies of similar focus are based in the developed economies where stronger implementation framework exists for green building. Besides, they are mostly based on evaluation of green certified buildings using few criteria. This study differs in that it presents the existing building sustainability practices in a less pronounced green property market, with varying architectural styles using more robust criteria. Information provided is applicable in Nigeria and other emerging economies.

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Changing human lifestyle and increasing urbanisation are contributory factors to the high demand for concrete construction materials across the globe. With the imminent developments in the unpopulated marine/coastal zones, higher installation of concrete facilities is still expected. However, poor design and construction procedures coupled with inadequate materials selection and exposure to aggressive environmental conditions, such as chloride laden environments, often result in the reduced aesthetic and structural performance of concrete. Deterioration of reinforced concrete structures located in a coastal/marine setting can influence the safety, economic, and sustainability aspects of society. Hence, there is an increased need for alternate binder systems with the ability to reduce the effects of chloride attack in concrete. This paper presents a critical review of the engineering properties of metakaolin (MK) based concrete exposed to chloride attack. The key advantages and limitations of using MK for concrete production purposes were outlined and evaluated. Areas for future research were also highlighted in this paper. Based on the favourable 28-day compressive strength (73–84 MPa) and durability performance documented across the numerous past year studies that were reviewed, it can be concluded that MK is a viable alternate binder material for combatting chloride attack in coastal/marine concrete structures. This, in conjunction with its lack of chemical CO2 emissions, proves that MK can be used to improve the serviceability and sustainability states of marine structures. The viewpoint of this review will guide concrete constructors and researchers on a possible framework for the utilisation of metakaolin for enhancing durability concrete in aggressive environments.