11. Sealing existing structures

When, after a certain period of time, a structure reveals openings, cracks or fissures that could allow water or air to pass through, it can always be repointed or filled by various means.

Let's take a look at grouting in old buildings: as a result of drying, shrinkage, differential settlement of the soil, movement of the shell, etc., openings or cracks may appear in the shell or between facade elements. We then need to check whether the crack is alive or stabilized, for example by placing plaster witnesses to bridge the crack. If, after a certain time, these witnesses crack themselves, this means that the crack is continuing to open, and questions must be asked about the causes of this abnormal movement, which could continue until the building is seriously damaged. If, on the other hand, the plaster witnesses crack and then close again as a function of temperature...