Cooling energy-saving potential of a green roof in Brazilian climates

Luan Maximiano de Oliveira da Costa, Frederico Romagnoli Silveira Lima, Marcela Alvares Maciel and Raquel Diniz Oliveira

doi:10.22712/susb.20220031

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2022 Vol.13, Issue 4 Preview Page Next Page

General Article

Cooling energy-saving potential of a green roof in Brazilian climates

30 December 2022. pp. 414-435

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Abstract

The objective of this study was to investigate the cooling energy-saving potential of a green roof under different climates comparing green roofs with concrete slabs in Brazil. Eight cities were chosen to represent distinct conditions, according to the Köppen-Geiger climate classification. A numerical simulation was carried out to analyze the roof energy-saving potential for an office building, based on Sailor’s vegetated rooftop model. A sensitivity analysis was performed using a paired t-test and multivariate factorial analysis and considering the leaf area index (LAI) and substrate layer thickness. The results showed that significant annual cooling energy savings were achieved by the green roof for 6 of the 8 climate classifications analyzed. Since the substrate layer thickness was not as relevant as the LAI, the green roof strategy could also be used for building retrofits, with the optimal composition being a substrate layer thickness of 5 cm and LAI equal to 5.00. As a key finding of this investigation, the cooling energy-saving potential of the green roof strategy was verified under all distinct climates tested in Brazilian territory. Through these results, its performance and benefits were highlighted and quantified, considering the most important design parameters that could achieve this goal.

Keywords

cooling energy savings

green roof

concrete roof slab

statistical analysis

subtropical climate

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Information

Publisher :Sustainable Building Research Center (ERC) Innovative Durable Building and Infrastructure Research Center
Publisher(Ko) :건설구조물 내구성혁신 연구센터
Journal Title :International Journal of Sustainable Building Technology and Urban Development
Volume : 13
No :4
Pages :414-435
Received Date :2022. 09. 13
Accepted Date : 2022. 10. 25
DOI :https://doi.org/10.22712/susb.20220031

International Journal of Sustainable Building Technology and Urban Development ISSN:2093-761X(Print) 2093-7628(Online)

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