Heat insulation and water prevention integration building roof and construction method thereof

The invention relates to a heat insulation and water prevention integration building roof and a construction method thereof, relating to the technical field of building. So-called integration firstly means heat insulation and water prevention function integration and secondarily means that a seamless integral roof is formed through a cast-in-site construction method so that the building roof has better heat insulation and water prevention effect. The heat insulation and water prevention integration building roof comprises a heat insulation tile layer and a water prevention layer sandwiched infoam concrete. The heat insulation and water prevention integration building roof is characterized in that the heat insulation tile layer is positioned on the lowest end of the building roof and formed by overlapping heat insulation tiles, and overlapping positions are provided with water-stop groove faces; and the water prevention layer is formed by casting polystyrene foam concrete on the heat insulation tile layer in site and then strickling, then spraying high molecular polymer emulsion and then coating waterproof paint in a strickling way, then paving waterproof roll materials and finally casting the foam concrete in site. The invention is not only suitable for severe cold regions in the national north, but also suitable for extremely hot regions in the national south and also has the advantages of low project cost, easy construction process operation, wide material source and suitability for wide popularization.