An insulative blanket is sized and shaped to cover a dock leveler deck and the gaps between the deck and a surrounding dock platform to prevent the transfer of heat through the deck or across the gaps. A batten structure is combined with the blanket such that the combination forms a relatively rigid structure which can be easily placed and maintained in its desired position. The combination is raised and lowered by an attached line and a suspended overhead container is provided to further collapse the combination as it is raised and stored within the container.