A multiple layer drain seal device for rapidly sealing the apertures in a drain grate, the drain seal having a lower sealing layer and an upper protective cover layer, the lower sealing layer being separable from the upper protective cover layer except at discrete attachment points, wherein the lower sealing layer is softer, more flexible and has lower shear resistance than the upper protective cover layer, such that the lower sealing layer sags into the drain grate apertures but the upper protective cover layer does not.