Protocolo para ensaios de absorção térmica de materiais alternativos para a construção civil

Abstract

The energy expenditure for temperature control in buildings has increased in recent decades and the materials used in buildings have a direct influence on their thermal performance. It is not uncommon for newly constructed buildings to adopt the installation of air conditioners in their environments. The study of the thermal properties of alternative materials with insulating characteristics can contribute to breaking paradigms and changing the reality of construction, providing thermally efficient buildings. In this context, this work aimed to define a thermal test protocol for reconstituted wood panels and drywall to determine a minimum sample size that ensures the determination of the thermal absorption and heat transfer properties between environments when these materials are used as thermal insulators in buildings. We used commercial plasterboard, plywood, and OSB (Oriented Strand Board) panels. We performed scanning electron microscopy (SEM) of the panels. We determined the densities of the panels, which were subjected to thermal testing in a set of thermal chambers with temperature controlled by a PID controller. We calculated the thermal conductivity of the panels based on the information obtained with the thermal test. In conclusion, to meet the thermal conductivity value of 0.35 W/mºC for drywall, 0.15 W/mºC for plywood, and 0.14 W/mºC for OSB, the sizes of the specimens must be between 20x20cm and 30x30cm for plasterboard and plywood and between 10x10cm and 20x20cm for OSB panels.