VISUAL IMPACT OF ADDITIONAL SHADING ELEMENTS ON FAÇADE OF HISTORICAL BUILDING – A CASE STUDY.

A long term EU effort is to reduce CO2 emissions in order to stabilize climatic changes. Reducing buildings energy consumption is a necessary step to achieve this goal. Since 2020 all new buildings in Czech Republic must be designed as nearly zero energy. It sets low energy consumption requirements as well as requirements on indoor environment quality. However one third of residential buildings in Czech Republic was built before the year 1945 and does not meet these demands. Refurbishments of these buildings should be done with respect to their historical-cultural value. Sun-shading elements can influence indoor quality in multiple ways, primarily by reducing room overheating, as well as they can influence façade composition and architectural look of the building. Visual impact of chosen shading elements was explored. The article is divided into two main sections. In the first section a questionnaire focused on inhabitants of buildings built before the year 1945 that was conducted in order to determine whether they experience overheating, which shading devices they use, if any and what would they expect from potential refurbishment is evaluated. Nearly all respondents are using internal shading elements and experiencing overheating. The results were arranged into charts. The second section focuses on a case study of assessment of visual impact of shading elements on façade of chosen not-yetrefurbished historical residential building. A residential building in Mladá Boleslav built in the mid 1920’s was chosen as a suitable example. Important principles of façade composition were described. Several shading elements were assessed in terms of visual impact on façade composition in relation to described composition principles with regard to indoor environment quality. Shading elements with the most significant positive influence on indoor environment have also the most significant negative visual impact. [ABSTRACT FROM AUTHOR]