Wind loads for U.S. building designs are specified in a publication of the American Society of Civil Engineers (ASCE 7). Portions of the current version, ASCE 7-10, rely on wind tunnel tests that date back 30-50 years. In recent decades, advances in computer technology have allowed the simultaneous recording of many more pressure taps than was possible before. This research proposes a step-by-step methodology which determines the external pressure coefficients (GCp) on the components and cladding of low-rise buildings using modern aerodynamic wind tunnel databases. Pressure tap time history data is used to calculate the peak pressure coefficients for a comprehensive sweep of arbitrarily selected grid areas, over all available tested wind directions. By incrementing grid area combinations with their contributing taps, GCp can be plotted versus effective area. External pressure coefficients for the analysis of cladding and components are under predicted by the current ASCE 7-10 specifications.