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 .