Building Construction: Structural Members, Walls & Envelope Terms

column

Long, slender supporting pillar, usually loaded axially in compression

beam

Horizontal member that carries a load across and transfers it to columns and walls

girder

Large principal beam (steel, concrete or wood) supporting other members at isolated points

joist

Horizontal support for a floor or ceiling; lumber 2 or 4 in thick, 6+ in wide, or steel/aluminum equivalent

load-bearing wall

Wall designed to support an imposed load in addition to its own weight

anchor bolt

Threaded bolt embedded in a foundation to secure a sill, framework or machinery

envelope

Extreme outside surface and dimensions of a building

wythe

Each continuous vertical section of a wall one masonry unit thick

tilt-up

Concrete members cast horizontally near final position, tilted into place after forms are removed

metal framing

Metal framed partitions for fire-rated construction around columns and at beams

dampproofing

Water-resisting treatment on a concrete or masonry wall surface against water or moisture

air barrier

Envelope component that stops air leakage and reduces condensation risk (house wrap)

sheathing

Plywood, OSB or lumber closing up walls, floors or roofs before finishes

flashing

Thin impervious sheet that prevents water penetration or directs water out (hips, valleys, masonry walls)

vapor barrier

Material that stops vapor or moisture passage and prevents condensation within assemblies

bond breaker

Material that prevents adhesion between fresh concrete and the substrate

storefront sash

Assembly of light metal members forming a frame for fixed-glass storefront

curtain wall

Exterior closure or skin of a building; nonbearing, not supported by beams or girders

veneer

Masonry facing attached to the backup but not bonded to act with it under load

lintel

Horizontal member above an opening (window, door) that carries the wall above