Hello, I need you to guide me, my old house has leaks from the terrace, my idea is to fix it once and for all. It is a very old house. The quickest and cheapest option would be to pass a liquid membrane to the terrace, the issue is that the duration is limited, so I am thinking of lifting the entire terrace, the issue is that I don't know what I am going to find. Please correct me what I am going to say next, unless you are saying a silly one: The flat roof of a new building has the following layers: Slab, polyethylene film as a vapor barrier, thermal insulation of expanded polystyrene, subfloor with slope, folder with water repellent (1: 3 ratio (one of three sand cement + ceresite), asphalt paint primer, asphalt membrane with the caulked joints, another asphalt paint hand or a liquid membrane hand, protection folder / seat, ceramic floor or tile. So far am I doing well or did I make a mistake? The issue is that I will find when breaking the terrace of an old building from the 40s or 50s ... as I realize how far to break, etc. Is it broken until asphalt paint is found? Once that point is reached, all the remains of asphalt paint are removed, I paint again, I place a membrane that turns around at the ends and gets into the wall (drool), a liquid membrane hand, a seat folder is remade by last, the ceramics are placed with double gluing method. Is all this correct? Greetings and thanks!

Everyone has their system; mine is to reach the slab, repair possible cracks with special repair mortar Basf or any other brand; place 2 asphalt fabrics of 3 or 4mg / m2, each one, sbs quality, the first one without adhering on the ground but yes on the perimeters and the second one adhered to heat to the previous one (the asphalt fabrics, by themselves, already make the vapor barrier function)