Avaliação de fatores climatológicos no telhado verde de edificação no bairro do Recife

Abstract

The Green Roofs provide benefits in urban environments such as improved environmental quality by reducing the impacts that result from green area suppression throught reducing ambient temperature, increasing relative air humidity and retaining and delaying the flow of rainwater to the gallery rainwater system, functioning of vegetable gardens and creating spaces for sociability. This study aims to evaluate the efficiency of the green roof model installed in a building as an alternative to improve the environmental quality in the city of Recife through climatological studies and with the specific goals of comparing the difference in temperature and relative air humidity between two distinct surfaces in the same slab of the Information Technology Business Center, in the Recife Neighborhood (Recife Antigo) and to point out the use of the green roof model adopted as an option for buildings that did not provide vegetated constructions on their slabs. The climatological data records were made using two datalogger ux100-003 sensors to read temperature and relative humidity measured by comparative data in the month of January 2017, (the dry season), and the month of June 2017, (the rainy season), with data reading through the bhw-pro-cd software for datalogger programming and data reading. The slab areas were divided into two spaces. The sourthern face, wich its larger, received the living space with benches, tables, chairs and ceramic vases with vegetation propor for environmentsof intense sunstroke, wind and breeze influence and a strip of grass as a belt around the entire perimeter of the southern face to the effect of the landscape quality and heat reduction in the space. In the northern faced area grass was instover this, 2 cm layer of substrate composed of black earth mixed with decomposed material derived from vegetables, used for planting the grass. The results indicated that air temperature of in the month of January differs by 2.4° C more in the sensor located on the face facing south; the amplitude of the minimum relative humidity of the air differed in 19,63% in relation than the environment with face towards the north. This showed greater heating of the ceramic floor and greater humidity in the environment with grass. The minimum temperature in the month of June was insignificant in the sensors located in the two spaces knowing that external factors such as sea and land breezes, rains, gust of wind and clouds may have interfered in this environment. Regarding the average thermal discomfort index for the month of January, the maximum for the lawn environment was 27.8º C, while in the environment with a ceramic floor was 31.1º C, indicating that the vegetal cover softens the thermal discomfort. Although the structure of the vertical garden consists only of the filtering layers, one of 2 cm substrate and one of vegetation, it is evident that the green roof with a lawn had greater efficiency in heat absorption, temperature reduction and increase in relative air humidity, proving its effectiveness in buildings that did not predict the use covers on their roofs. Improving environmental quality in cities requires solutions that soften the island's effect from heat by providing a reduction in the rate of thermal discomfort. The green roof is indicated as an option for restitution of green areas removed by the construction and urban development sector. The indication of the green roof as a roof of the buildings works to soften the ambient temperature, contributes to improve the quality of life and the thermal comfort for the inhabitants of the city.