Layout evaluation of large capacity warehouses

Purpose - The purpose of this article is to present a model to estimate and evaluate the operational costs of alternative layouts for large capacity warehouses or distribution centers with a large variety of goods. Design/methodology/approach - The proposed model is based on time and resources studies per each of the basic activities on a warehouse operation. For validation purposes, the proposed model was applied on a perishable goods warehouse in Mexico. The output data was compared to actual data. Performance measures were operational costs and average picking time. Findings - It was found that the proposed model is robust, flexible, simple and easy to be implemented. The model was used to evaluate two new alternatives of layout and operations of the same warehouse. It was found that the option with the layout with docks on long opposite sides of the warehouse and the operation without a separate picking zone minimizes operational costs. Research limitations/implications - The richness of the model is strongly supported by the information the warehouse has about its operation. With knowledge of the process, it is required to distinguish deterministic from stochastic basic activities and develop distance computations that depend on the layout being studied. Practical implications - The approach used to model warehouse operations was to estimate the movements and resource consumption per commodity. This allows the model to be used in every operational context when the complexity of the system is strongly dependent on and proportional to the volume of operations. In addition, it is particularly adequate as a tool to compare average performance measures of different scenarios for the same system. Originality/value - The model proposed here provides a simple way to estimate particularly operational resource consumptions and picking times as proxy measures for efficiency and efficacy of a warehouse. It uses distance computations, time information and unit occurrence frequencies of basic activities over a single commodity in the system.