Emissivity Measurements of Common Construction Materials

This paper will review and discuss the determination of the emissivity of common construction materials to aid the investigator during infrared inspections/surveys of building envelope systems. Specifically, this paper will discuss the results of product testing of constructed wall assemblies. The wall assemblies are constructed to mimic the common materials encountered in building envelope surveys. They include materials such as hardboard lap siding, stone veneers (faux and natural), stucco, exterior insulation and finish systems (EIFS), trim accessories, vinyl frames, painted flashings, self-adhering flexible flashing membranes, oriented strand board (OSB), ethylene-propylene-diene monomer (EPDM roofing material), wood framing, and concrete. In order to provide a better analysis and determination of results with thermography measurements it is important to understand the relationships of the products emissivity on multi-surface, multi-material constructed assemblies. As well, the thermographer should understand the effects of the angle of inclination utilized when conducting thermographic surveys. This paper will deal with the determination of the values of emissivity of such common materials and the effect of the angle of view used at the time of the thermographic imaging.