Simulation-based method to determine climatic energy strategies of an adaptable building retrofit façade system

Vast amounts of the European residential stock were built with limited consideration for energy efficiency, yet its refurbishment can help reach national energy reduction goals, decreasing environmental impact. Short-term retrofits with reduced interference to inhabitants can be achieved by upgrading facades with elements that enhance energy efficiency and user comfort. The European Union-funded Meefs Retrofitting (Multifunctional Energy Efficient Façade System) project aims to develop an adaptable mass-produced facade system for energy improvement in existing residential buildings throughout the continent. This article presents a simplified methodology to identify preferred strategies and combinations for the early design stages of such system. This was derived from studying weather characteristics of European regions and outlining climatic energy-saving strategies based on human thermal comfort. Strategies were matched with conceptual technologies like glazing, shading and insulation. The typical building stock was characterized from statistics of previous European projects. Six improvements and combinations were modelled using a simulation model, identifying and ranking preferred configurations. The methodology is summarized in a synoptic scheme identifying the energy rankings of each improvement and combination for the studied climates and façade orientations.