An adhesive formulation having an adduct of an epoxy resin and an elastomer, a phenoxy epoxy hybrid resin supplied as a solution formed by dissolving a phenoxy resin in a liquid epoxy resin to form a pre-formed dissolution product, a core/shell polymer, and one or more additional epoxy resins. The adhesive formulation may include a curing agent, blowing agent, filler, accelerator, or a combination.