The invention discloses an intumescent flame-retardant belt material for buildings and belongs to the field of building fire protection devices. The intumescent flame-retardant belt material applies to pipeline fire protection and comprises an intumescent flame-retardant belt, wherein the outer surface of the intumescent flame-retardant belt is coated with a casing, a support frame is mounted on the outer surface of the casing, a hoop is mounted outside the support frame, and clamp plates are distributed on upper and lower end surfaces of the hoop and make contact with end surfaces of the intumescent flame-retardant belt, the casing, the support frame and the hoop; the support frame is formed by inverted V structures uniformly distributed around the outer surface of the casing, and gaps are formed between adjacent inverted V structures and in internal spaces of the inverted V structures; a plurality of auxiliary intumescent holes are formed in the intumescent flame-retardant belt, andheat conducting bars are mounted in the auxiliary intumescent holes. The novel foam type flame-retardant belt material for the buildings is high in flame retardant efficiency, intumescent efficiency,intumescent capacity and self-stability, quite high in size adaptability, highly water-resistant and cement-resistant.