The method for calibration of a single point laser system used in a measuring system for wood boards in a sawmill includes the steps of storing two orthogonal dimensions of a calibration bar, the values of the two dimensions being different from each other; placing the calibration bar within the scan zone of the measuring system, which is between two opposing lasers; measuring the distance to the calibration bar from each laser in a first dimension, and rotating the bar to its orthogonal dimension and again measuring the distance to the bar from each of the lasers. The distance information to the calibration bar and the known dimensional values of the bar in the two dimensions are then used to determine that a calibration bar is present rather than a wood board to be measured. If the presence of a calibration bar is confirmed, then the distance values and the dimension values are used to determine the actual distance between the two lasers. This information is then compared with the last known laser distance to provide calibration information for the system.