Moisture detection in wood and plaster by IR thermography

in the last decade ,many research have been carried on the application of IRT to detect moisture in the materials of historical buildings, but only few studies are comprehensive of IRT application on wood. The thermal characteristics of timber are highly different from the porous materials ones; particularly, the thermal capacity of wood is lower than bricks, stone and mortars. LAboratory researchers and scientific literature determined that the water content detection in porous materials is more related to the evaporation rate of the surfaces and the presence of soluble salts than to the absorption capability of the materials. Moreover a corretaltion between moisture content, evaporation and boundary conditions, was studied by analyzing evaporation fluxes at different environmental conditions and water content. Because of the lower heat capacity of the timber, the thermographic shot aftern the heating can be affected by the influence of water presence. Laboraotry tests and study cases shoe the advanteges and limit of IRT techniques, and the results obtained permit the comparison between the different heating system applied.