A soffit is a section of ceiling that is dropped well below the underside of the roof or floor above. What it creates is an enclosed space above the ceiling, often filled with heating and cooling ducts, wires, or cables.

A soffit is most often designed for an architectural affect - the dropping of the ceiling helping to create an area of space differentiated from other areas. Soffits can also be exterior and the term is also employed to describe the ceiling-like underside of extended eaves.

Soffit is from French: 'soffite', formed as a ceiling; and directly from 'suffictus' for suffixus, Latin: 'suffigere', to fix underneath.

It’s most commonly used around a building’s main roof, but soffit can also be used under porches, under arches or columns, under a flight of stairs; anything that has a visible ceiling. It is commonly made in aluminum and vinyl, as well as fiber cement, wood, and steel.

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