Roofline

Roofline is used to describe the fascia, soffits, bargeboards, antefixes and cladding that forms the frontage immediately below the roof and the eaves of many homes and buildings. These are traditionally made from wood, but can be made of a variety of different materials, including plastic, such as polyvinyl chloride.

Fascia is a term used in architecture to refer to a frieze or band running horizontally and situated vertically under the roof edge or which forms the outer surface of a cornice and is visible to an outside observer. This is to say that the long dimension of the surface is horizontal and the short dimension is vertical. As the literal meaning is "band" it is also used, although less commonly, for other such band-like surfaces like a wide, flat strip around a doorway, different and separate from the wall surface. The word fascia derives from Latin "fascia" meaning "band, bandage, ribbon, swathe". The word is pronounced with the "long-a" sound, /ˈfeɪʃə/, rhyming with the Japanese word geisha.

Specifically, used to describe the horizontal "fascia board" which caps the end of rafters outside a building, which can be used to hold the rain gutter. The finished surface below the fascia and rafters is called the soffit or eave. A soffit is also often installed between the ceiling and the top of wall cabinets in a kitchen, set at a 90 degree angle to the horizontal soffit which projects out from the wall.

In classical architecture, the fascia is the plain, wide band across the bottom of the entablature, directly above the columns. The "guttae" or drip edge was mounted on the fascia in the Doric order, below the triglyph.

In steep-slope roofing, a board that is nailed to the ends of a roof rafter; sometimes supports a gutter. In low-slope roofing, the horizontal trim located at the perimeter of a building is usually a border for the low-slope roof system.

Soffit (from French soffite, formed as a ceiling; directly from suffictus for suffixus, Latin suffigere, to fix underneath), in architecture, describes the underside of any construction element.

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