The invention relates to a cement-based multilayer assembly that can be used as a biological support for building façades or other structures, said assembly comprising an optionally newly-installed structural concrete layer (1), an anchoring layer (2), a biological layer (3) made from a cement-based material and a waterproofing cladding layer (4) with cavities (5) in which the biological layer (3) is in direct contact with the environment. The biological layer (3) is made from conventionally produced concrete or mortar including a retarder- or acid-type chemical additive with a pH between 5.5 and 8, or from an MPC cement (Magnesium-Phosphate Cement) having a phosphate source and a magnesium source. The biological layer (3) includes aggregates of the siliceous or expanded clay type, the maximum size of which not exceeding one quarter of the thickness of the layer.
