Development and Testing of Environmentally Friendly Envelope for Energy Efficient Buildings in the Czech Republic

Abstract

In many countries of Central Europe is a stock of existing buildings from 1950's to 1980's featuring original panel curtain walls. These envelope structures are now at the end of their service life and thus replacement solution is needed.There are various replacement alternatives such as aluminium, steel or steel-plastic panels, but these structures have typically high amounts of embodied energy and carbon footprint. Within national research project Intelligent Buildings, Czech Technical University in Prague has developed a timber-based curtain wall system called Envilop. The paper presents its development and laboratory testing. Properties of Envilop were proven by modeling, calculations and experiments inline with actual standards on curtain walls systems and in addition life cycle assessment (LCA) was performed. Heat and moisture simulations proved that does not suffer from thermal bridges and has U-values at levels suitable for passive housing; air tightness testing proved high quality of design. LCA calculations compared the system to aluminum-based alternative and show significant potential to savings in embodied energy and carbon footprint by using Envilop.