The purpose: The graduation thesis deals with the problem of the transition of heat and humidity through diffusion-open and diffusion-closed constructional complexes of the outer wall made from natural materials.
The methodology: With online program Ubakus, we analyzed 9 constructional complexes (CC) of an exterior wall made from natural materials. After entering all parameters, we receive information about quantity of condensation, time of drying of the condensation, moisture in the wood, the thermal transmittance, the thermal stability and surface temperature in the winter and summer seasons. The results were compared with the criteria according to the Rules on efficient use of energy in buildings with a technical guideline (OJ. RS, no. 52/10) and TSG-1-004: 2010. In the winter season, we are made 5 examples of CC: example 1; load bearing construction from CLT (Cross-Laminated Timber), example 2; DHF (High Density Fiberboard) panels, example 3; OSB (Oriented Strand Board) panels, example 4; promoted diffusion-open construction complexes and example 5; optimized diffusion-closed construction complexes made for the winter season. Optimized CC and promoted CC was also analyzed during the summer season (Example 6 and 7). In the winter season, we checked the moisture and heat transfer where we installed OSB panels inside and DHF panels to the outside of CC (example 8). In example 9, we analyzed changed position of OSB and DHF panels.
The results and discussion: With a larger thickness of thermal insulation, we get adequate thermal transmittance. In case of comfortable internal conditions and non-extreme external conditions, diffusion-open construction complexes are more universal. In a diffusion-open CC (Example 4) 0,51 kg/m2 of condensation in extreme winter climate conditions are produced. In the summer season at extremely high temperatures and humidity (Example 6), CC 0,12 kg/m2 condensate is produces. This quantity dries in summer in 6 days. The diffusion-closed CC (Example 7) is unuseless in summer days with 2,53 kg/m2 of condensation, because CC need 233 summer days for drying a quantity condensate. Incorrect installation of OSB panels, resulted 0,38 kg/m2 of condensation and need 124 days for dries in summer days. In a planned installation of panels 0,28 kg/m2 of condensation is produced with a drying time of 7 days. After replacement a wood panels, functionality of CC is different. When the humidity or air temperature of the interior spaces is increased, we get an unuseless construction complexes because, we don't have enough warm days.
Conclusion: The analyzes were performed only for the exterior wall construction complexes. In the same way, we can analyze other segments of the building envelope.
When we are planning a new CC, we must check the construction complexes performance in different external and internal conditions and optimize CC to operate in the most unfavorable conditions.
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