Análise de desempenho térmico de forro e subcobertura em bambu na região do semiárido

Abstract

The roofing is defined as an important way of heat exchange between the internal and external areas of the building. The use of an efficient roofing with an affordable and feasible ceiling or under-coverage can solve huge problems caused by the high levels of the user thermal discomfort during the hot and dry periods of a certain place. This way, a detailed study to identify possible materials which may promote lower numbers of thermal amplitude and thermal amortization may contribute to the thermal performance of the material to the roofing. In this context, the bamboo appears as an alternative which presents many advantages, such as high resistance, fast growing and high performance. Besides, it is a natural and low-cost biodegradable element, which does not require specialized labor, and it is easily found in the region of Arapiraca, Alagoas. The main purpose of this research is to identify and potentialize the advantages of the bamboo (Guadua paniculata) as an under-coverage and ceiling facing the conventional systems of roofing (ceramic tile and fiber-cement tile) in the climatic context of the semiarid of Alagoas, which is hot and dry. As a method, it was elaborated a systematic review of literature on the search platforms Web of Science and Scopus with a timeline of 30 years, about the use of bamboo on civil construction and the monitoring of time data of internal and external surface temperature of roofing, ceilings and under-coverage, besides the internal air temperature in the attic and in the interior of the test cell. The results found present the use of under-coverage to the semiarid climatic context as feasible for both of the types of analyzed roofing, achieving an average difference of surface temperature of 7.8 °C and 15.3°C in absolute terms at midday, when the sun was in the highest position. In addition, the fixed ceiling without the use of under-coverage can be recommended only for the roofing with ceramic tile. The internal air temperature (under the ceiling) achieved an average difference of 0.8 °C with the ceramic tile (comparing to S-BF with the testimonial cell), while on the fiber-cement roofing, this average difference achieved 1.6 °C, highlighting that the air temperature in the S-BF was hotter than the cell in this testimony. The use of bamboo as a ceiling and under-coverage was an efficient strategy to avoid thermal amplitude inside the internal environment, which is an important aspect to obtain thermal comfort, which may also contribute to the esthetic and environmental urban quality. Above all, it is possible to highlight the influence of the roofing, in which the cell with the under-coverage presented good results of thermal amortization between the cells with bamboo under-coverage and ceiling compared to the testimonial test cell.