Gable Roof

A gable roof is the simple pitched roof with two slopes rising from opposite walls to meet at a horizontal ridge. The triangular portion of end wall enclosed by the two slopes is the gable. It is one of the most widespread roof forms in the world and is also called a ridged, saddle, span, peaked or dual-pitched roof.

Variants

• Front-gabled: the gable faces the street, so the ridge runs perpendicular to it. Typical of Gothic-era German town houses and of American gablefront houses from the early 1800s to about 1920.
• Side-gabled: the eaves face the street, with the ridge parallel to it.
• Cross-gabled: two or more gable roofs intersect, usually at right angles, forming T, L or more complex plans with valleys at the junctions.
• Box gable: the gable is enclosed as a separate element with boxed ends.
• Shaped, Dutch and crow-stepped gables: decorative parapets that hide the sloping roof line behind curves or steps; common in the Netherlands, Belgium, Scotland and eastern England.
• Clipped or jerkinhead gable: the top of the gable is cut off by a small hip.

Advantages

• Simple to frame with rafters or common trusses and inexpensive to build.
• Sheds rain and snow well, and accommodates nearly every roof covering.
• Produces usable attic space and allows windows in the gable walls.
• Gable ends are convenient places for attic ventilation louvres.

Weaknesses

Gable-ended roofs perform less well than hipped roofs in hurricane- and tornado-prone regions. Wind striking the flat gable wall, and uplift along the rake edges, can peel off roof sheathing and cause the gable wall to collapse. Building codes in high-wind regions therefore require bracing of gable end walls and stronger connections at the rakes. Wide overhangs at the rake also increase uplift.

Global use

Steep gable roofs are typical of snowy or rainy climates and traditional thatched, tiled and shingled buildings across Europe, North America and East Asia. The A-frame is an extreme form in which the roof slopes reach nearly to the ground.