An underlayment system is provided that includes a plurality of protrusions that extend from a common base member. The protrusions and base member can include an opening therethrough that allows for subsequent layers of material, such as adhesive, to interact and bond to each other. The protrusions are arranged in such a way to contain a wire, string, or heating element, within a receiving area. The arrangement of the protrusions allow for routing of the wire, string, or heating element in a variety of angles, bends, and other routing layouts.