ResearchWood technology
Building forensics

Building forensics

The field of research of building forensics was founded in 2012 by Prof. Rapp. As a starting point, optical techniques from classical forensic science were transferred to questions of ​​structural damage, further developed, adapted and refined for construction practice. Since then, numerous research projects have been carried out at the IBW on issues from various application areas, e.g. wood species identification, detection of invisible mould, past water damage, fluorescence of minerals, conservation, vehicle damage diagnosis and more.

The main methods of optical building forensics are absorption imaging analysis and fluorescence imaging analysis in the ultraviolet (UV), visible (VIS) and near-infrared (NIR). Materials with very similar properties can thus be distinguished non-destructively. This also includes changes due to aging or past water exposure, mould growth and contamination.

Horse Chestnut (Aesculus hippocastanum) contains the blue fluorescent Aesculin. It dissolves easily in ethanol/water. Here visualised by irradiation with a forensic UV light source. Image: F. B. Peters
Nothing abnormal can be seen on the ceiling with the naked eye (left). However, the method of optical building forensics reveal by means of excitation with blue light (right) that the left half of the ceiling is almost completely overgrown with mould. Image: A.O. Rapp
Rubber components on polyurethane sealer leave fluorescent traces. Here visualised by means of excitation with UV light. Image: F. Peters and A.O. Rapp