Wall stud

A wall stud is a vertical framing member in a building's wall of smaller cross section than a post. They are a fundamental element in frame building.

Stud is an ancient word related to similar words in Old English, Old Norse, Middle High German, and Old Teutonic generally meaning prop or support. Other historical words with similar meaning are quarter and scantling (one sense meaning a smaller timber, not necessarily the same use). Stick is a colloquial term for both framing lumber (timber) and a "timber tree" (a tree trunk good for using as lumber (timber)). Thus the names "stick and platform", "stick and frame", "stick and box", or simply stick framing. The stud height usually determines the ceiling height thus sayings like: "...These rooms were usually high in stud..."

Studs form walls and may carry vertical structural loads or be non load-bearing such as in partition walls which only separate spaces. They hold in place the windows, doors, interior finish, exterior sheathing or siding, insulation and utilities and help give shape to a building. Studs run from sill plate to wall plate. In modern construction studs are fastened to the plates in a way, such as using ties, to prevent the building from being lifted off the foundation by severe wind or earthquake.

Studs are usually slender so more studs are needed than in post and beam framing. Sometimes studs are long, as in balloon framing where the studs extend two stories and carry a ledger which carries joists. Balloon framing has been made illegal in new construction in many jurisdictions for fire safety reasons because the open wall cavities allow fire to quickly spread such as from a basement to an attic; the plates and platforms in platform framing providing an automatic fire stop inside the walls, and so are deemed much safer by fire safety officials. Being thinner and lighter, stick construction techniques are easier to cut and carry and is speedier than the timber framing.

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