The article presents tests of wooden elements fromhistoric rafter framing of the barracks for prisoners in the Auschwitz II – Birkenau Extermination Camp. Within the framework of the research project realized at the Cracow University of Technology, non-destructive strength tests were performed which determined a security level of the element considering high conservation requirements. The second stage of the research involved the strengthening by sticking carbon fibre belts into the cross-section of original rafters dismounted from barracks for prisoners and the comparative analysis toward strengthened reference sample. Laboratory tests performed on rafters from barracks with strengthening used in the form of carbon belts showed an in crease of bearing capacity to bending by 5%. It is not a significant increase of the bearing capacity in a global scale, but for individual elementswhich have a larger cross-section, bearing capacity after strengthening may be higher than 5% shown in laboratory conditions.
Keywords: historic rafter framing, Auschwitz-Birkenau Concentration Camp, non-destructivewood testing, strengthening of wooden elements.