m2 Application of a single-layer waterproofing membrane adhered to the poor concrete layer and sprayed so that it adheres to the foundation slab, formed by a self-adhesive waterproofing sheet, which acts as an anti-gas barrier such as methane and radon and consists of an elastomeric mastic (SBS), with a high-density polyethylene (PE) film reinforcement adhered to a 50-micron aluminum sheet on its upper face, and an easily removable siliconized film finish on the underside, type TEXSELF GS 1.5 (LBA-15-AL+PE), placed with previous primer, type EMUFAL PRIMER with a minimum endowment of 300 g/m2, separating layer with thermo-welded non-woven geotextile of high mechanical performance, composed of 100% polypropylene for use in building and civil works, type TEXXAM 1500, ready to receive concreting.