Hanger strips for securing insulation material to a surface of a structure formed of sheet metal material including a plurality of bases which are connected by one or more breakable tabs integrally formed between each pair of adjacent bases and wherein first open slots extend from each of the breakable tabs toward opposite side edges of the bases and wherein a shank extends from each of the bases in a common direction and wherein pluralities of strips are oriented in first and second assemblies of rows of strips having their shanks opposing one another and their bases overlapping one another such that tips of the shanks are safely enclosed between the bases of the opposing assemblies and seated within the first open slots.