Methodology and platform for NZEB renovation of residential buildings

Renovation of the existing building stock is a vital part of reaching upcoming energy savings and CO2
emission targets. The European Union (EU) continuously publishes directives and guidance to support the
transition of existing buildings to nearly-Zero Energy Buildings. A method for calculation of cost-optimal levels
for minimum energy performance was introduced in 2012. Its aim is to compare and select different
renovation alternatives, based on energy savings and global costs. It has been successfully applied on a
package level; however, its complexity has restricted it from being used for comparing renovation alternatives
between single components with the same and different functions. This paper presents a methodology for
determination of a simplified value linking economical and efficiency parameters on a component level. The
value allows for fast overview of cost-benefit of different renovation alternatives between components and
systems. It serves a decision-making aid for compilation of renovation packages, which are further evaluated
with the cost-optimal approach. The paper also introduces novel refurbishment assessment platform that can
assist decision makers with fast compilation of refurbishment packages incorporating key aspects of the
presented methodology. The current functionality of the platform is showcased at the end of the paper by a
case study.