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IEA-EBC Annex 56 - A56 opt

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A56 opt - Tool to support decision making for cost-effective energy and CO2 emissions optimisation in building renovation


A56opt-tool was developed in the framework of the International Energy Agency’s Energy in Buildings and Communities (IEA EBC) programme Annex 56: “Cost-Effective Energy and Carbon Emissions Optimisation in Building Renovation”. It aims at supporting calculations based on the Annex 56 methodology allowing comparing and evaluating different packages of renovation measures using simulation data that come from other tools (energy performance, costs and environmental impact) and include the capacity to evaluate also the relevance of the co-benefits.


The Annex 56 methodology provides the basis for the assessment  and evaluation of energy related renovation options. The methodology considers a life cycle approach and takes into account not just the energy use and carbon emissions, but also the embodied energy and the overall added value that may come to the building from a renovation process. In this sense and based in the energy consumption of each renovation measure, this tool allows to compare renovation options, considering the global costs, the embodied energy, the energy use during the operation period and the co-benefits of each renovation measure.  In order to use this tool it is necessary to introduce: 


  1. key information on each country's energy conversion factors, carbon emissions 'conversion factors and the predicted evolution for the energy costs;
  2. key information on each renovation options related to energy use, Building integrated technical systems’ (BITS') efficiency, different types of costs (investment, maintenance, replacement, energy and disposal) and impact of the materials involved in the renovation package.

Concerning the impacts, the Annex 56 methodology allowed a simplification of considering just the impact of the production and transport of the materials, once these two indicators are the ones with higher impact in the Life cycle impacts analysis (LCA). For the calculation of the impacts is necessary to know the amount of each material involved in each renovation measure.


For further information or to download the tool, please visit the relevant IEA-EBC Annex 56 webpage at the link provided below.