A Combined Insulation - Waterproof Construction Using Light Insulation Mortar and Waterproof Material and Method Thereof

The present invention provides a combined insulation and waterproof structure using lightweight insulation mortar and a waterproof material. The present invention has just two layers to allow easy construction, can minimize a load on a building for safety improvement, and can maximize waterproof and insulation effects. The combined insulation and waterproof structure using lightweight insulation mortar and a waterproof material according to the present invention contains lightweight insulation mortar that is directly applied to a rooftop floor surface and consists of 100 parts by weight of Portland cement, 65 parts by weight of white cement, 40 parts by weight of silica, 40 parts by weight of pealite, 30 parts by weight of clay, 15 parts by weight of calcium carbonate, 7.5 parts by weight of ethylene vinyl acetate (EVA) power resin, 0.75 parts by weight of dispersant, and 0.75 parts by weight of water-reducing agent; and a waterproof material that is directly applied to the lightweight insulation mortar and consists of a mixture of one or more of a polyurethane waterproof material, a polyurea waterproof material, an inorganic elastic coating water proof material, and a sheet-type waterproof material. The lightweight insulation mortar has a compression strength of 250 to 300 kgf/cm2, a specific gravity of 1.3 to 1.5, and a heat conductivity of 0.02 to 0.04 W/(m.k). The water-reducing agent is produced by using poly alkyl glycol carboxylate powder with a viscosity of 300 cps, a residue on evaporation of 50 to 55%, a specific gravity of 1.09 to 1.11, and a pH of 2.5 to 4.