Giorgos Petrou, UCL student who joined the London-Loughborough (LoLo) EPSRC Centre for Doctoral Training in Energy Demand in 2016, presented part of his MRes research at the 38th AIVC Conference in Nottingham. The work tried to establish whether a modeller’s choice of Building Performance Simulation (BPS) software can influence the level of overheating risk predicted by the method described in CIBSE’s Technical Memorandum 59. The results revealed significant differences for seven out of the nine models simulated in two BPS tools, EnergyPlus and IES VE, with IES VE predicting a lower overheating risk than EnergyPlus in all cases. The main drivers for the observed differences were revealed to be the modelling of wind-driven natural ventilation and surface-convection. The implications of this work relate to both the consistent prediction of overheating risk across the industry and research which is based on the use of BPS tools. This project has been supervised by Dr. Anna Mavrogianni, Dr. Anastasia Mylona (CIBSE), Dr. Rokia Raslan, Mr. Gurdane Virk (Atkins) and Prof. Mike Davies.