How an integrated diagnostic approach can help in a correct evaluation of the state of preservation of waterlogged archaeological wooden artefacts

► More than 200 waterlogged archaeological samples analysed. ► Several investigation techniques were used to make a reliable diagnostic evaluation. ► Single techniques can be misleading because of wood collapse or high ash content. ► Integrated approach helps to correctly evaluate the artefact state of preservation. ► Possibility of a reliable material grading and, in future, of a tailored treatment.