Measuring units, load handling devices, storage and retrieval systems, and methods function to determine alignment of a grid framework structure in a storage and retrieval system. The grid framework structure includes a supporting framework structure upon which is mounted to a track system that supports remotely operated load handling devices for handling storage containers stacked in storage columns under the grid framework structure, and guides for guiding storage containers in a storage column when lifted or lowered by the load handling device. Related measuring units and load handling devices and storage and retrieval systems are disclosed. The method includes moving a measuring unit within a storage column in a vertical direction, guided by a set of guides. Each distance sensor is used to measure the distance between it and one guide, and the measured distance(s) are used to determine whether the set of guides is misaligned.