Thermal performance of coupled cool roof and cool façade: Experimental monitoring and analytical optimization procedure

The cool roofs in buildings is a promising option to deal with summer Urban Heat Island (UHI) effects. In context to that, studies on different cool roof materials are widely available; however, there is a dearth of studies on insulating material benefits and implication for tropical and sub-tropical climate zones. This work investigates thermal performance, energy savings and cost benefits of cool roof materials. For this study, simulation of various cool roof materials such as Marble, Expanded Polyurethane Spray (EPS), Poly Vinyl Chloride (PVC), Spray Polyurethane Foam (SPF) , Extruded Polystyrene Foam (XPS), Thermocol sheet, Asphalt tile, Gypsum tile and Jumbolon-board have been carried out using Energy Plus software package. The results of zone air temperature show that maximum zone air temperature occurs in the month of May. The maximum zone air temperature obtained for conventional roof is 32.1oC, whereas that for Thermocol sheet, SPF, XPS, Jumbolon-board, EPS, marble, PVC, Asphalt tile and Gypsum tile is 28.8, 28.9, 28.8, 29, 29.1, 31.9, 30.5, 30.2 and 30.7oC respectively. Conventional roof surface outside and inside temperature difference is 2.90C, whereas, roof surface outside and inside temperature difference for Thermocol sheet, XPS, Jumbolon-board, SPF, EPS, marble, PVC, asphalt tile and gypsum tile is 9.2, 9.3, 8.7, 7.5, 8.1, 3, 3.1, 3.3 and 2.20C, respectively. Notably, XPS, Thermocol sheet, SPF, Jumbolon-board, EPS, Marble, PVC, Asphalt tile and Gypsum tile cool roof materials can save around 5.47, 5.38, 5.35, 5.15, 4.93, 1.09, 2.62, 2.31 and 2.18 MWh annually, respectively for the selected building. The payback period for marble, PVC, gypsum tile and asphalt tile is above 1 year, whereas the effective payback period obtained for XPS, Thermocol sheet, SPF, EPS and Jumbolon-board varies from 3 to 6 months. It is concluded that the cool roof materials may be used effectively to save energy and cost.

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Thermal Performance of a "Cool Roof" Attic Design

10.23953/cloud.iestoc.162 ◽

2017 ◽

Author(s):

José B. Dávila ◽

Keyword(s):

Thermal Performance ◽

Cool Roof

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CLAY ROOFING TILE: A COOL ROOF?

Open Journal of Science and Technology ◽

10.31580/ojst.v1i1.151 ◽

2018 ◽

Vol 1 (1) ◽

pp. 1-3

Author(s):

Anumah, Lesado

Keyword(s):

Cost Saving ◽

Surface Temperature ◽

Thermal Performance ◽

User Preference ◽

Natural Clay ◽

Night Time ◽

Cool Roof ◽

Significant Difference ◽

Colored Tile ◽

Clay Tile

The aim of this study is to determine if the clay roofing tile in its natural albedo can be considered â€œcoolâ€ in the thermal performance through a comparison of its surface temperature to a cool coated clay tile using the exposure rack method. It begins with highlighting the expectation (from review) of the thermal performance of a cool colored tile and comparing the surface temperature (maximum, mean and minimum) of the tiles. Day and night time temperature behaviors were also compared using graphs on excel software. A python t- test of means was also carried out to determine if there was any significant difference in the performance of the materials. It was found that the performance of the clay tile in its natural albedo is a cool tile in its thermal performance. The implication of this is a cost saving strategy. However, further research is needed as a form of coating may be needed in order to enhance its life span. A non- color coat whose only function is to protect the surface of the tile. This does not in any way disregard the use of coated tiles as user preference may still tend towards non- natural clay colored tiles, its purpose is to encourage informed cheaper methods of achieving cool roof strategies

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Thermal Performance Test of a Phase-Change-Material Cool Roof System by a Scaled Model

Advances in Civil Engineering ◽

10.1155/2018/2646103 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Suk Goo Yoon ◽

Young Kwon Yang ◽

Tae Won Kim ◽

Min Hee Chung ◽

Jin Chul Park

Keyword(s):

Temperature Distribution ◽

Low Temperature ◽

Surface Temperature ◽

Phase Change ◽

Phase Change Material ◽

Thermal Performance ◽

Room Temperature ◽

Roof System ◽

Cool Roof ◽

Change Material

General cool roof is effective for reduction of cooling load, but it has a problem of increasing heating load. Therefore, the purpose of this study is to complement the disadvantages of the cool roof system by utilizing phase change characteristics of phase change material (PCM). The study was carried out to verify the thermal performance of the PCM cool roof system by measuring the temperature on the top and bottom of the PCM cool roof system by making a miniature model (600 × 600 × 600 mm). PCM was inserted and not inserted, and the temperature difference according to the finish color (brown and white) was compared. As a result, the plate surface temperature using PCM was lower than that without PCM, and time-lag of temperature increase occurred. As a result of the comparison of temperature according to the finish color (brown and white), white showed a low temperature distribution up to 16.35°C. Even at room temperature, white maintained a low temperature distribution of 5.40°C than brown. The use of PCM cool roof system in roof finishes could lower the surface temperature and keep the room temperature low.

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The Effect of Cool Roofs on the Achieving of Energy Conservation with the Administrative Building Spaces

Association of Arab Universities Journal of Engineering Sciences ◽

10.33261/jaaru.2020.27.3.012 ◽

2020 ◽

Vol 27 (3) ◽

pp. 112-124

Author(s):

Duaa Faal Niama ◽

Ghada Mohammed Kammou

Keyword(s):

Energy Conservation ◽

Urban Environment ◽

Thermal Performance ◽

Fossil Fuels ◽

Research Problem ◽

Building Envelope ◽

Conservation Of Energy ◽

Cool Roof ◽

Cool Roofs ◽

The Impact

The world has gone beyond the realization that fossil fuels are a depleted energy source, that the earth is going through a global warming phase, and that it is important to find the necessary energy alternatives, with the least environmental impact, and to address energy consumption in the building sector in particular. Passive systems and their use, or combined with effective systems. due to the dependence of the Iraqi urban environment on the electricitySignificantly and the source of fossil fuel, it is important to find suitable solutions, especially in the summer because of high temperatures and increased drought, by taking advantage of the experiences of countries within this scope, and applied to buildings , Because the roof is the main source of thermal gain inside the buildings it is necessary to take the systems of cool roofs, which is a passive system in the roofing of buildings, contribute to improving the internal environment and achieve the thermal comfort of the occupants, the research problem was:"There is no clear conception of the possibility of applying cool roof systems in the local administrative buildings" and The objective of the research is to" clarify the importance of achieving the concept of conservation of energy and improve thermal performance through the application of cool roof systems in the administrative buildings in the urban environment of Iraq with a hot- dry climate, "and then ensure the research Two aspects,first one:The concept of thermal performance and conservation of energy in administrative buildings and the way of achieving energy conservation using cool roofs, while the practical side included: the handling of several global experiences of sustainable administrative buildings used cool roofs and indicate the impact of this system on the efficiency of thermal performance, The research concluded that it is possible to apply cool roofs in claimte of Iraq (hot-dry) because the cool roof has the ability to reflect a large amount of solar radiation falling on the surface of the roof, thereby reducing the thermal gain of the building and improve the thermal performance of the administrative building envelope, and as a result achieved Save energy within its spaces

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A Study on the Comparative Review of Cool Roof Thermal Performance in Various Regions

Energy and Built Environment ◽

10.1016/j.enbenv.2021.03.001 ◽

2021 ◽

Author(s):

Mohan Rawat ◽

RN Singh

Keyword(s):

Thermal Performance ◽

Cool Roof ◽

Comparative Review

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Effectiveness of Nanomaterial in the Roof of the Building to Achieve Energy Conservation for Indoor Environment of the Building

Journal of Engineering ◽

10.31026/j.eng.2021.02.09 ◽

2021 ◽

Vol 27 (2) ◽

pp. 126-148

Author(s):

Duaa Al-Ali ◽

Ghada M.Ismael Kamoona

Keyword(s):

Energy Conservation ◽

Thermal Performance ◽

Indoor Environment ◽

Building Materials ◽

Theoretical Aspect ◽

Research Problem ◽

Building Envelope ◽

Cool Roof ◽

Long Time ◽

Energy Consuming

The construction sector consumes large amounts of energy during the lifetime of a building. This consumption starts with manufacturing and transferring building materials to the sites and demolishing this building after a long time of occupying it. The topic of energy conservation and finding the solution inside the building spaces become an important and urgent necessity. It is known that the roof is exposed to a high amount of thermal loads compared to other elements in a building envelope, so this needs some solutions and treatments to control the flow of the heat through them. These solutions and treatments may be achieved by using nanomaterials. Recently, nanomaterials have high properties, so that this made them good elements to the strategy of energy conservation in the architectural field. Accordingly, the research problem lay in "the lack of studies that deal with strategies to use nanomaterials in the roof of the building (especially the administrative building) in order to achieve energy conservation within its spaces". Then the research aims to: "Determine the efficient of nanomaterials in the roof to improving the thermal performance and achieving energy conservation in the indoor environment of the buildings in Iraq". This research's theoretical aspect has focused on using nanomaterial and their applications in roof systems. While in the experimental aspect, an administrative application to test a mass of identical administrates building in the design. In this research, simulation of the standard roof with nanomaterial, cool roof, and standard roof systems has been done using the Ecotect program. The results obtained in this research showed that the nanomaterial affected the thermal performance and achieved the indoor environment's quality by reducing to energy-consuming in the administrative building in the hot-dry climate of Iraq.

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