SLBas saves up to 90 percent of the time needed for insurance inspectors, realtors and others to calculate the square area, perimeter and actual living area of a structure over manual methods. Using only the keyboard, the user creates a printable copy of a field drawing on the computers screen. SLBas can display the segment lengths of the drawing, work in either U.S. or metric units, and include policy/project, comments and date information about the drawing for later printing. The user can adjust for an attached garage, and a multi-story structure.