NUMERICAL SIMULATION OF DYNAMIC MOISTURE SPREAD IN COMPACT FLAT ROOFS
Keywords:
dynamic evaluation, compact flat roof, moisture content, WUFI 2D softwareAbstract
The contribution is focused on the numerical verification of the correct design of compact flat wooden roofs in the external boundary conditions of Central Europe (Vienna – Bratislava); the internal boundary conditions of the analysis met the requirements for human habitation. Using the WUFI 2D software, the compositions of compact flat roofs were analyzed using a vapor barrier and a variable vapor retarder with a low dispersion of diffusion thickness values and a variable vapor retarder with a high dispersion of diffusion thickness values. Each of these three compositions was assessed in versions without shading and with shading of the surface (by graveling the roof covering from the exterior side). The length of the analyzed period was 5 years. The main goal was to verify the accumulation of moisture in layers of the structure and whether critical moisture conditions suitable for the formation of molds and fungi causing rot will be reached in any of the compositions. The measurement results showed the different functioning of compact flat wooden roofs depending on the shading, as well as other conclusions for the design and realization of the composition of compact flat wooden roofs.
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