In this study, the effects of introducing vertical ventilation paths on the thermal and wind environments in city blocks were investigated using computational fluid dynamics (CFD) simulations. In particular, the effects of two vertical geometric parameters of the buildings, i.e., the average height of the buildings and the standard deviation of the building heights, in the windward region on the pedestrian thermal and wind environments in both the windward and leeward regions were quantitatively evaluated. In the windward region, the standard deviation of the building heights in the region was more effective for improving the pedestrian thermal environment. On the other hand, the average height of the buildings in the windward region affected the pedestrian thermal environment in the leeward region more than did the standard deviation of the building heights in the windward region. Furthermore, the correlations between the space-averaged air temperature and wind velocity at the pedestrian level were different in the windward and leeward regions. In the windward region, the correlation became negative, while a positive correlation was observed in the leeward region.
