I will build my house and the slab will be 50cm from a well that is usable. Is not the slab too close to the well? Are there any special precautions to take?
There have always been houses built near a well, and even houses with an internal well! A well if it is well done, is not a diffuser of moisture, except of course if it overflows, something that remains rare and usually results from a lack of maintenance (too full clogged). There is no particular warning about your slab. However, make sure that the capillary break imposed by the current rules of construction (DTU 20-1), is well made at the base of your walls. This is valid for all new constructions and avoids capillary rise.
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