In the case of historic frame buildings, the consequences of erroneous repair decisions or negligent maintenance lead to irreversible processes of deterioration of the building. Effective undertaking of rescue measures then requires carrying out appropriate diagnostic research. The results of these examinations will allow to propose repair solutions that do not interfere with the historical architectural and structural layout of the building. This paper will present the results of the assessment of the technical condition of the 17th century church in Sękowice, built in traditional frame technology. As a consequence of earlier inappropriate decisions concerning the renovation works, a considerable part of the wooden construction elements underwent biological corrosion, whichmade themlose their original strength properties. Some of the walls settled on the corroded foundation beams, and the uneven settlement caused twisting of the whole structure.