In virtual reality (VR), Impossible Spaces allow rooms to overlap each other in physical space, enabling developers to better utilize the limited space available for VR systems. Prior work has explored detect thresholds for an impossible spaces, but little work has considered how impossible spaces affect users’ understandings of spatial relationships within virtual environments. We present a study evaluating how impossible spaces affected participants’ judgments of a room’s width, and how this was impacted by whether participants considered each room individually, or within the context of the entire space. Participants’ judgments of single rooms was not impacted by being in an impossible space, however judgments were significantly smaller when considering an impossible space as a whole. Even so, participants’ judgments preserved the respective ratio between overlapping rooms, indicating that the relative sizes of different rooms is preserved in impossible spaces. This suggests that while absolute spatial information may be disrupted by impossible spaces, important relative information can be preserved. However, it is not yet clear how much of this effect can be attributed to lower-level perception and higher-level cognition.