Disclosed are various embodiments of expandable barriers. Expandable barriers are typically barriers made from an expandable material and formed to fit within a cavity. After being placed inside a cavity, expandable barriers generally undergo an activation process, where the expandable barrier expands to fill the cavity and create a physical barrier. Using various extrusion processes to form an expandable barrier allows for a reduction in tooling costs, while also allowing more flexible barrier designs. Such designs can be specifically tailored for a particular cavity or cavities to ensure that the barrier fills the cavity after expansion.