Field Evaluation of Indoor Microclimates of Green and Bare Roofed Urban Buildings at No-Ventilation Condition in a Sub-Saharan Climate
American Journal of Civil Engineering
Volume 2, Issue 6, November 2014, Pages: 143-151
Received: Nov. 20, 2014; Accepted: Nov. 30, 2014; Published: Dec. 2, 2014
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Authors
Sadiq Abubakar Gulma, Department of Civil Engineering, Pan African University, Institute for Basic Sciences, Technology and Innovation (PAUISTI), P. O. Box, 62000-00200, Nairobi, Kenya
Stephen Nyarindo Ondimu, Biomechanical and Environmental Engineering Department, Jomo Kenyatta University of Agriculture and Technology (JKUAT), P. O. Box, 62000-00200, Nairobi, Kenya Nairobi, Kenya
Patrick Ajwang, Biomechanical and Environmental Engineering Department, Jomo Kenyatta University of Agriculture and Technology (JKUAT), P. O. Box, 62000-00200, Nairobi, Kenya Nairobi, Kenya
Wariara Kariuki, Depertment of Horticulture, Jomo Kenyatta University of Agriculture and Technology, JKUAT, P. O. Box, 62000-00200, Nairobi, Kenya
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Abstract
There is a growing use of green roofs on urban buildings around the world with a focus on reducing energy consumption of buildings. Energy consumption of buildings results mostly from heating or cooling of indoor spaces. When mechanical air conditioners are operating, windows (natural ventilation) are shut. This paper studied 2 field models, one with a living green roof and the other left bare (conventional), both without any sensible or latent heat loss or gain via their ventilation systems. Microclimatic data was collected at the field for the 2 rooms for a period of 25 days. Two microclimate parameters, air temperature and relative humidity which determines the highest effect on indoor thermal comfort were compared for the two models and with the ambient conditions. Result shows that both air temperature and relative humidity of the room with the green roof were lower than the bare roofed house. Fluctuations were also minimal for the green roofed urban building.
Keywords
Green Roof, Bare Roof, Evaporative Cooling, Cooling Loads, Building Energy
To cite this article
Sadiq Abubakar Gulma, Stephen Nyarindo Ondimu, Patrick Ajwang, Wariara Kariuki, Field Evaluation of Indoor Microclimates of Green and Bare Roofed Urban Buildings at No-Ventilation Condition in a Sub-Saharan Climate, American Journal of Civil Engineering. Vol. 2, No. 6, 2014, pp. 143-151. doi: 10.11648/j.ajce.20140206.11
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