First-grade waterproof system for basement part of building and construction method of first-grade waterproof system

The invention discloses a first-grade waterproof system for a basement part of a building and a construction method of the first-grade waterproof system. A C15 concrete cushion is sequentially provided with cement gel, a 1.5-thick double-side CPS-CL reaction bonded polymer wet-spread waterproof roll, a 50-thick C20fine aggregate concrete protective layer and an anti-permeable reinforced concrete floor from bottom to top to form a floor; a permeable reinforced concrete side wall is sequentially provided with cement gel, a 1.5-thick double-side CPS-CL reaction bonded polymer wet-spread waterproof roll, a 1.5-thick single-side CPS-CL reaction bonded polymer wet-spread waterproof roll and a 10-thick polyethylene composite insulation board protective layer to form an external wall; a permeable reinforced concrete roof is sequentially provided with cement gel, a 1.5-thick double-side CPS-CL reaction bonded polymer wet-spread waterproof roll, a 1.5-thick single-side CPS-CL reaction bonded polymer wet-spread waterproof roll, a 1.5-thick high-density polyethylene (HDPE) geomembrane, a 0.4-thick PE membrane isolating layer and a 70-thick C20 concrete protective layer to form a roof.