Tell-tale

Tell tales are a simple and cost-effective method to find out whether a crack moves. A gypsum strip is fixed across the crack. In case the crack widens, the tell-tale will crack; in case the crack narrows, the tell-tale will be damaged or will detach from the underground; displacements of the crack flanks against each other are shown by the tell-tale as well. For a sound documentation, the tell-tales should be numbered, dated, and each single control (time; measured values; climate for outside tell-tales; etc.) should be recorded.