The Impact of Different Passive Roof Construction Types on Building Thermal Performance / Experimental Method for Optimizing the Thermal Performance of Building Enclosures

Buildings are large consumers of energy worldwide, responsible for roughly 40% of the world’s primary energy consumption. In regions with hot climatic conditions such as Iraq, a substantial portion of energy goes to building space cooling loads. Although all components of the building enclosure are in contact with the external environment, the roof experiences the highest temperature fluctuations. Roof surfaces account for 20-25% of the total urban surface area and can be utilized to minimize the air and surface temperatures of urban areas. The impact of solar radiation on clear days and the loss of heat during the night all affect the roof more than any other component of the building. The research in this dissertation demonstrates an extensive investigation that examined four passive roof construction technologies as a means of improving the indoor thermal conditions under summer conditions. Five identical Smart Test Cells (STCs) representing a section of a typical Iraqi dwelling unit were constructed for the experimental research of the study. In this research, the roof was the only envelope parameter that changed among the STCs. Four types of roofing technologies, Exterior Reflective Cool Coating (ERCC), Radiant Barrier (RB), Interior Radiation Control Coating (IRCC) and Phase Change Material (PCM) were individually applied to each STC. The STCs were tested under two scenarios: (1) Without-Ventilation and (2) With-Ventilation. For both scenarios, the thermal performance was evaluated by recording and analyzing the temperature sensors across the roofs, ceilings and indoor air temperatures. When comparing the Without- Ventilation tests to the With-Ventilation tests, the results demonstrated that natural ventilation had a significant influence on the thermal performance of the STCs. Herein lies the potential advantages of employing natural ventilation. The under ceiling surface temperatures and indoor air temperatures were greatly improved by stack effect, which uses convection to exhaust rising hot air and draw cooler low level air into the STC. The findings of this research can assist in selecting more appropriate roofing technologies for building envelopes and thus contribute to the reduction of cooling loads and building energy consumption.

Grantor dc:publisher

University of Kansas

Year dc:date.issued

2017

Author dc:creator

• Alyasari, Haider I.

Advisor dc:contributor.advisor

• Chang, Jae D

• Architecture
• Architectural engineering
• Energy
• Building Enclosures
• Passive Roof Construction
• Test Cells
• Thermal Performance

Statement dc:rights

• Copyright held by the author.

Language dc:language.iso

en

Dc Identifier Other

http://dissertations.umi.com/ku:15199

OAI identifier oai:identifier

oai:kuscholarworks.ku.edu:1808/37331