Overhead expenses are costs that are necessary for running a business, but are not directly related to the production of goods or services. These expenses include roofing, hats, and RENT. ROOF is a four letter word meaning the covering of a building, typically made of tiles, metal, or other material. HAT is a three letter word meaning a covering for the head, typically with a brim all around. RENT is a four letter word meaning a payment made periodically by a tenant to a landlord in return for the use of land, a building, an apartment, an office, or other property.