Building façade renovation with prefabricated panels requires the installation of supporting connectors. Obtaining the exact locations and angles of the connectors is currently a time-consuming activity. The new method presented in this paper uses AprilTag markers as targets on the wall and measures them based on a photogrammetry concept. The 3D coordinates of the targets are estimated by our algorithm, and then we can obtain the location and direction of each connector. Current results are promising but still need some improvement. Our goal is to measure the exact position and angle of each marker, and the error should not exceed 1mm at about 10m away from the building. This objective is not reached in this paper, but latest advances show very close results.