Disclosed herein is a sealing assembly for moving a slidable panel for engagement with and disengagement from sealing means, the sealing assembly comprising a linkage assembly which connects a handle and at least one roller assembly having roller wheels, the sealing assembly being configured to be adjustable, by manipulation of the handle, such that the at least one roller assembly and the slidable panel supported thereby are movable between a first position where the slidable panel is in contact with sealing means thereby providing weatherproofing and a second position where the slidable panel is free of the sealing means and the panel is able to move freely relative to an outer frame, and wherein the linkage assembly is configured to as to provide a variable force through the handle when the at least one roller assembly and supported panel is moved between the first and second positions.