Structural condition assessment of in-service wood

The various techniques used in the assessment of the condition of wood in a building, are discussed. A structural condition assessment consists of, a systematic collection and analysis of data pertaining to the physical and mechanical properties of materials in use; evaluation of the data collected; and providing recommendations, based on evaluation of the collected data, regarding portions of an existing structure that affect its current or proposed use. A variety of techniques such as visual, resistance drilling (probing), and stress wave or ultrasound-based techniques, are used to assess the condition of wood in structures. The inspector observes the structure for signs of actual or potential deterioration, noting areas for further investigation, in case of visual inspection. Resistance drilling, an automated form of mechanical probing, is used to characterize wood properties and to detect abnormal physical conditions in structural timbers.