Blocking, often called backing, also refers to pieces of wood or other material that run between wall studs in order to provide support and attachment sites for mounted hardware or trim such as cabinets, shelving, handrails, vanity tops without a cabinet underneath, bathroom accessories, TV mounts, and moulding.
Properly installed blocking is easier to find and use for attaching wall hardware than studs alone. Once drywall, or any other material, covers the wall it can be difficult to find 2×4 studs for attachment, and the position of nails and screws must be adjusted to stud location. Thus, if blocking is installed at a uniform and predetermined height, attachment sites can be found without using a stud finder, and the blocking can be utilized anywhere along a wall at that height. This is particularly useful for installing upper cabinets or shelving as they tend to be fairly heavy and finding appropriate studs for installation can be difficult.