Soffit

Definition

A soffit is the underside part of a member of a structure, such as a beam, stairway, roof, or arch. It is the undersurface of a horizontal element of a building, especially the underside of a stair or a roof overhang.

Purpose

The purpose of a soffit is to provide a finished appearance to the underside of architectural elements, protecting structural components and improving aesthetics.

Examples of Use

• Residential homes often have soffits under roof overhangs to protect rafters and enhance curb appeal.
• Commercial buildings use soffits to conceal HVAC ductwork and other utilities in ceilings.
• Soffits in stairways provide a clean, finished look to the underside of the stairs and can incorporate lighting fixtures.

Related Terms

• Fascia: The vertical finishing edge under the roof eave.
• Eave: The part of the roof that overhangs the walls of a building.
• Ceiling: The upper interior surface of a room, often incorporating soffits for aesthetic or functional purposes.

Notes

Soffits can be made from various materials, including wood, aluminum, vinyl, and composite materials, chosen for durability, maintenance, and appearance.

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