I have a terrace of 125m ² (tower house, terrace and carport) where the slab has been redone (hedgehog, polyane film, slab 15 cm). She is perfectly level. Is it necessary to make a screed before laying the tiles or can I do it directly?
DTU 26.2 (Unified Technical Document), which specifies good construction practices, states that "the surface condition of screeds or slabs must be fine and regular", which is rarely the case with a concrete slab. This does not generally have a surface quality or sufficient flatness to directly stick a tile. In addition, the direct bonding on the date does not allow to respect the expansion joints, essential for any surface greater than 40 m2. The realization of a screed is therefore unavoidable for you.
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