Building member height measuring device

The utility model provides a building member height measuring device and belongs to the field of building measuring instruments. The device structurally comprises a primary scale column and a secondary scale column, wherein a primary scale sleeve and a secondary scale sleeve are respectively sleeved on the primary scale column and the secondary scale column; a supporting beam is arranged between the primary scale sleeve and the secondary scale sleeve; the right upper end of the supporting beam is hinged with the primary scale sleeve, and the left lower end of the supporting beam is hinged with the secondary scale sleeve; positioning wheels are arranged at the hinged parts between the supporting beam and the primary scale sleeve, and between the supporting beam and the secondary scale sleeve respectively; the positioning wheels are connected through a chain; a scale needle with a rack vertically penetrates through the primary scale sleeve and is matched with a rocker positioning device on the primary scale sle