In the present study an enhanced variant of the big bang-big crunch (BB-BC) technique, namely exponential BB-BC algorithm (EBB-BC) is developed for code based design optimization of steel frame structures. It is shown that the standard version of the BB-BC algorithm is sometimes unable to produce reasonable solutions to problems from discrete design optimization of steel frames. Hence, through investigating the shortcomings of BB-BC algorithm, it is aimed to reinforce the performance of the technique for this class of problems in particular. The study provides numerical evidences of how the performance of a well-known metaheuristic technique (BB-BC) can significantly be improved through simple yet effective modifications in its formulation to achieve a more robust and reliable variant (EBB-BC). Further, a comparison of the optimum solutions with those of other well-known metaheuristics reveals that the EBB-BC algorithm can efficiently be used as a novel tool for code based design optimization of steel frames. (c) 2012 Elsevier Ltd. All rights reserved.