Determining the Thermal Transmittance Coefficient of the Opaque Façade Wall Element Using Non-Invasive Method

Prior to building retrofitting, thermal performance assessment of the building is essential. An adequate assessment can provide useful insights to heat-losses and envelope anomalies i.e. thermal bridges, mold, air infiltration etc. The most important physical quantity that needs to be defined is the thermal transmittance (U-value) which is the key factor in determining the transmission heat loss coefficient HT, as well as in determining the building's energy efficiency. In the absence of documentation, experimental methods are the only solution to identifying such parameter. This paper makes overview of experimental methods; and presents an example of non-destructive method by using Quantitative Infra-Red Thermography (QIRT) in service of calculating U-value of the opaque façade wall element.