Thermal performance of green envelopes in buildings in the Brazilian southeast

Abstract The evaluation of the thermal performance of buildings using green roofs, living walls or green walls as envelope protection elements is a very important tool for architects and engineers to minimize heat gain, provide better thermal condition and improve thermal performance. This paper presents three different studies of thermal performance of buildings with green cover: 1) a case study of a green roof, 2) an experimental study of a living wall, and 3) a case study of a green wall; all of which include comparative and concurrent measurements between exposed surfaces and surfaces protected by vegetation. The parameters measured were air temperature, relative humidity, air speed and mean radiant temperature, as well as the inner and outer temperature of the walls. Those analyses led to the conclusion that the use of vegetation as a protection element on roofs and façades acts positively on the heat flows in the envelope, representing an important tool for passive thermal control of high temperatures inside the buildings.

摘要：采用绿色屋顶、活墙或绿墙作为围护结构保护元素来评估建筑物的热性能，对于建筑师和工程师而言，是降低热增益、改善热环境和提升热性能的重要工具。本文阐述了三项关于具有绿色覆盖层建筑热性能的研究：1）一项关于绿色屋顶的案例研究；2）一项关于活墙的实验研究；3）一项关于绿墙的案例研究；所有研究均包含了暴露表面与植被保护表面之间的对比和同步测量。测量的参数包括空气温度、相对湿度、空气流速以及平均辐射温度，以及墙体内外温度。这些分析得出结论，将植被作为屋顶和外墙的保护元素，对围护结构中的热流产生积极作用，是被动控制室内高温的重要手段。