Method of manufacturing a building element based on a hydraulic binder, an element thus obtained, and a building method using such elements

A building element in the form of a hollow rectangular block made by molding under pressure a mixture of a hydraulic binder, an inert granular fill and water, said building element having an inner space which is closed by a top face and opens out on a bottom face of the building element, said top face being provided with projections for longitudinal and transverse alignment and positioning, said bottom face including channels for passing a sealant and cavities for receiving the projections of the top face of an identical building element, said channels communicating with said cavities and said inner space, said building element further having longitudinal end faces wherein one of said end faces includes a vertical groove for casting a sealant, said groove having a bottom end opening out into one of said channels.