Pipeline layout is a significant factor influencing an area-wide layout. But in the most of published works, piping system only consists of the one-to-one connection pipelines with constant diameters. In addition, energy loss is sometime ignored in previous works. In this work, energy loss due to pressure loss and heat loss is taken into consideration originally. An improved method is proposed to design an industrial area-wide layout considering the optimization of pipe network. The pipe length of steam piping is optimized based on Kruskal algorithm. The diameters of steam piping are piecewise considered. The flow rates are obtained by solving a linear programming (LP) model. The problem of area-wide layout optimization is solved by genetic algorithm (GA). Finally, the results of a case study show that the optimization of piecewise steam piping can reduce the total flow rate and energy loss of all branches in the pipe network. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.