No, a chair rail does not make a room smaller. Chair rails are primarily used as a decorative element and to establish room proportions. They do not have a direct impact on the visual size of a room. However, the positioning of chair rails can create a visual effect that can make the room appear wider or taller depending on their placement. It's important to note that the perception of room size can be influenced by various factors such as lighting, color, furniture arrangement, and overall design choices.