CHAPTER ONE 1.0 INTRODUCTION 1.1 Background to the Study
Over the years researches has been carried out on how to improve thermal comfort within spaces and buildings with an emphasis on bioclimatic design principles (Hussaini, 2016), building materials such as double cavity walls (Musa, 2016) and building envelope design (Arowona, 2017), these studies were conducted on institutional typologies such as office buildings, hotels, recreation centers and so on. Previous studies also show a lot of work carried out on thermal comfort in residential typologies, (Akande and Adebamowo, 2010; Adaji and Watkins, 2015; Abdulkareem, Almaiyah and Cook, 2015). However, only little work had been carried out on Vertical Greenery Systems (VGS) in Nigeria which includes the works of Akinwolemiwa and Gwilliam (2015) and (Akinwolemiwa, Bleil de Souza,
De Luca and Gwilliam, 2018) which were carried out in the hot and humid climate of Lagos state. This the research therefore is focused on VGS in the hot dry climate of Nigeria to explore and investigate its application in this climate. Furthermore, there is a wide gap in research on the application of Vertical Greenery Systems (VGS) such as green walls to enhance thermal comfort in Nigeria (Akinwolemiwa and Gwilliam, 2015) as most works done are being carried out in Europe, Asia and the United States with climate such as the hot and humid or the temperate region.
The application of plants in buildings has been in existence for years as seen from the hanging gardens of Babylon (Dahanayake and Chow, 2017). As technology progressed, there are more effective and advanced methods of integrating these plants in buildings and thus the concept of Vertical Greenery Systems (VGS) came into being. VGS are structures that allow vegetation to spread over a building façade or an interior wall (Pérez, Cañero, Franco and Egea, 2016). It is mainly categorized into two based on the growing mechanisms which is the carrier and support (Jaafar, Said and Rasidi, 2011) and are also called living walls and green facades (Pérez, et al.,2016).