Perceived enclosure of space, angle above observer, and distance to boundary.

Most previous research suggests that the horizontal size of a space has a strong effect on the perception of enclosure, but Hayward and Franklin reported in 1974 that the main determinant of perceived enclosure was the ratio of boundary height (H) over the distance to boundary (D) rather than just the boundary height per se or distance per se. We attempted replication of that finding. Students (41 male, mean age=24.7 yr., SD=7.7) rated 16 images on a scale of open/enclosed. There was a strong effect on impressions of enclosure for angle above observer (r = .91), and this effect was larger than the effect of height (r = -.17), but there also was another strong effect for distance (r = -.68). Moreover, the effect of distance was dependent on angle above observer (r = -.52). Thus, partial replication was achieved, and a new relationship between the geometry of environments and perceived enclosure was identified.