a framing member incorporates a series of web slots along a portion of the member that are expanded through the process of manufacture . the expansion of the web slots creates voids and metal web elements in the webbed portion of the member , which can be a stud . the voids created during the expansion process can become the voids for running wiring , plumbing and heating ducts . the web elements can be designed to minimize thermal transmission from the exterior to the interior of a wall including the member , as well as provide adequate structure properties required from the structural member . the expanded slots allow the part to enlarge without increasing the amount of raw material and therefore substantially reducing the cost to manufacture .