In tropical regions like Singapore, balancing between IT thermal specifications and environmental essential parameters can be challenging. Additional considerations such as structural restriction of legacy data centres, budget limitation and prediction of future IT demand add on to the matrix of design parameters. CFD offers the possibility to evaluate several design parameters such as number of racks, allowable heat load, cooling systems and implementation of cold/hot aisle containments in a fast, accurate and low-cost manner. It is foreseeable that CFD will be an increasingly practical tool in optimizing the performance of future environmentally friendly and yet efficient data centres.