Lossless open-type building door

The utility model provides a lossless open type building door. The technical problems in the prior art are solved. Lossless open-type building door, the door comprises a secondary door and a primary door, an upper door stop is arranged above the secondary door and the primary door; a traction seat is arranged between the mother door and the upper door stop; the traction seat comprises an upper seat and a lower seat; the upper seat is fixedly connected with an upper door stop; the lower base is slidably connected with the main door through a sliding mechanism and can move up and down in a reciprocating mode along the main door. Wherein the upper seat is provided with a first connecting rod, the lower seat is provided with a second connecting rod, a plug-in type hinge structure is arranged between the first connecting rod and the second connecting rod, and the lower seat is further provided with a control mechanism capable of enabling the second connecting rod to be separated from the first connecting rod after