A roof panel includes a first member and a second member. A panel is attached to and interconnects the first member and the second member. The panel is configurable between a deployed configuration for attachment to a vehicle, and a stowed configuration for storage. The panel has a planar form when in the deployed configuration, and a rolled up form when in the stowed configuration. The panel may include an adjustable stiffness panel, such as a layer jamming panel, controllable in response to a control signal to exhibit a first stiffness when in the deployed configuration or the stowed configuration, or a second stiffness for reforming the panel between the deployed configuration and the stowed configuration.