The disclosure relates to a composting device including a housing defining an interior with an access opening providing access to the interior, a composter bin located within the interior and in communication with the access opening, and a cover slidably mounted to the housing and slidable along a sliding path between opened and closed conditions to selectively open and close the access opening. A seal assembly comprising a seal depending from one of the cover or the housing and a sealing surface provided on the other of the cover or housing about the access opening. The seal arranged such that a space between the seal and the sealing surface decreases as the cover is slid from the opened to the closed condition, and the seal abuts and compresses against the sealing surface in the closed condition to seal the cover relative to the housing.