Forecasting the Hygrothermal Condition of Partitions in a Thermally Modernized Historical Wooden Building—A Case Study

The paper presents select in situ and numerical investigations related to improving the energy efficiency of historic buildings. Using the case study of a historic timber building as an example, the procedure of the in situ investigation of its existing condition is presented. This procedure included measuring the moisture of the timber elements, determining the presence of fungi, mold, and wood-destroying insects, infrared camera inspection, and measuring the microclimate of the rooms. According to the conclusions of the building survey report, conservation guidelines were proposed. On the basis of those proposed guidelines, thermal upgrades were suggested, including insulation on the inside of the envelope components. Detailed numerical calculations were provided for the proposed thermal insulation systems. Those included a hygrothermal performance evaluation in the context of the change in the moisture content of timber elements in the insulated envelope components. The risk of mold development on the surface of selected junctions was also estimated. The key outcome of this study is a proprietary procedure for improving the thermal protection quality of envelope components of historic timber buildings.