Curtain Wall

A curtain wall is a non structural exterior building wall that keeps the weather out of the interior but carries no load beyond its own weight, transferring wind loads back to the frame through connections at the floors or columns rather than carrying the floors above it. Because it need not bear structural load, a curtain wall can use lightweight materials, most often an aluminum frame infilled with glass, though stone veneer, metal panels, louvres and operable windows and vents are also used. A curtain wall system is designed to span several floors at once, accounting for the building's own sway and movement, thermal expansion and contraction, seismic loads, water diversion and thermal performance in a way a single storefront window system does not need to. Historically buildings of timber or masonry, or a mix of the two, carried their own exterior walls as load bearing elements, which limited how tall a building could rise and how large its window openings could be; the curtain wall's separation of enclosure from structure removed that limit once steel and later aluminum framing became available. Oriel Chambers in Liverpool, designed by the architect Peter Ellis and completed in 1864, is recorded in the Guinness Book of Records as the earliest building known to use a metal framed glass curtain wall. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/