Construction method for waterproof renovation of railway metal roof

The invention relates to the technical field of railway roof renovation, and particularly discloses a construction method for waterproof renovation of a railway metal roof. The construction method comprises the following steps that firstly, the railway metal roof is derusted and decontaminated (if the derusting is not thorough, a layer of rust fixing prime coat is coated), then a prime coat is coated twice, then a liquid coiled material is brushed on detail nodes by adopting a one-cloth two-coating method, the liquid coiled material is sprayed integrally after a surface is dried, then a quick-setting waterproof coating is sprayed to form a waterproof layer, and finally a finish coat is coated selectively. Waterproof renovation of the railway metal roof is realized. According to the construction method for waterproof renovation of the railway metal roof, the difficult problem of base surface treatment of the rusted metal roof is solved, the cost of base surface treatment is reduced, the construction efficiency