Abstract: A chimney cap for protecting the upper open end of a chimney flue from the ingress of undesirable elements, such as squirrels, raccoons and birds or the like, is disclosed. The cap comprises a housing having four perforated sides which are detachably connected to one another in succession, the four sides each being formed from a flat metal blank provided with slots at one vertical edge portion and upturned tongues at the opposite vertical edge portion, the tongues of each perforated side projecting through the slots of an adjoining perforated side to thereby secure the perforated sides to one another and present a four-sided enclosure. The foregoing abstract is neither intended to define the invention disclosed, nor is it intended to be limiting as to the scope in any way.