With the global push to decarbonize the building sector and growing interest in occupant-centric building controls, numerous simulation and field studies have been conducted to explore the trade-off between energy efficiency and occupant comfort. These studies largely disregard individual differences in thermal comfort and assume each zone has a fixed occupancy schedule. In office buildings, there is often some leeway in how occupants are grouped and assigned to different building spaces (e.g., offices and meeting rooms). In this paper we investigate the extent of the impact of the space allocation strategy on the energy-comfort trade-off in office buildings, and whether it depends on specific building characteristics. Our simulation shows that varying the space allocation strategy in a medium office building can lead to over 3.5%/15.1% change in annual/monthly energy consumption, and over 15% change in average thermal comfort when using the personal comfort model. This finding calls for the joint optimization of HVAC operation and space allocation, possibly at different timescales.