Impact of climatic data uncertainties on the simulation of the thermal behavior of ancient houses

In many countries, the stock of existing buildings accounts for half of the energy consumption. With the actual environmental and energetic context, it is urgent to reduce energy consumption and greenhouse gases emissions in the buildings sector. In order to optimize retrofitting strategies, the thermal behavior of the existing buildings must be efficiently modeled by the dynamic building energy simulation tools. The stock of existing buildings is very important with, for instance, more than 30 millions of dwellings in France. This stock is characterized by a wide variety of construction techniques that are not taken into account in the existing calculation methods and tools as has been shown in a recent French study. This paper presents in the first part the uncertainties related to the thermal modeling of a traditional ancient house using different calculation tools. Then the house is modeled with the dynamic simulation tool TRNSYS in order to analyze the influence of the uncertainties of the climatic data on the quality of the results.