The emissivity and surface temperature of glossy materials are measured in IR thermography by covering the surface with a material with the known emissivity. The quantities can be, however, determined without using materials with the known emissivity. IR radiation is refl ected from the measured glossy surface and a thermographer detects such refl ection. This paper discusses the measurement of the surface temperature and emissivity of glossy materials which are used in external structures of the buildings -for instance, windows, light external walls or tiles. A four-point method is proposed for a more accurate determination of the surface temperature and emissivity of glossy materials. Results of successful laboratory and fi eld tests of the method are presented. Prinzipien der Vier-Punkt-Thermografi e-Messmethode für dieOberfl ächentemperatur und den Emissionsgrad glänzender Werkstoffe.

Determination of the surface temperature and emissivity of glossy materials is a complicated task due to the relatively wide range of emissivity values and the reflection of infrared radiation from surrounding objects. As a consequence, standard methods used in infrared thermography are not applicable. In this article, an alternative method is proposed for the measurement of the surface temperature and emissivity of glossy materials used in the external structures of buildings that is based on an external source of thermal radiation. It is shown that the method gives quite accurate values of emissivity of both low-and high-emissivity glossy materials, whereas the surface temperature of low-emissivity glossy materials is less accurate and strongly depends on the accuracy of the used thermal camera.

Microorganisms on the facades of buildings (eg, algae and cyanobacteria) are the harmful factors that cause destruction of the surface of building materials in exterior (facade paints, plasters, masonry, stone, concrete, etc.). One of the properties of listed biological factors is the production of thermal energy, which can vary in different species. Mentioned energy can be recorded using infrared thermography. The paper contains the results of the examined expressions of the biological pests on the insulated facades of the buildings using infrared thermography.

This paper deals with the comparison of the effect of the contact thermal insulation in the connection of the loggia slab to the stair wall of construction panel system T 06-B produced in Prefa Olomouc. Measurements took place in two panel houses, where parameters of internal and external air were measured. The thermally insulated building is compared with the untreated building. The temperature factor at the internal surface, which eliminates the boundary conditions of the measurement, was used as a comparative element. The measured values were statistically evaluated.

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