Backcloth
A flat (short for scenery flat) or coulisse is a flat piece of theatrical scenery which is painted and positioned on stage so as to give the appearance of buildings or other background.
Flats can be soft covered (covered with cloth such as muslin) or hard covered (covered with decorative plywood such as luan). Soft-covered flats have changed little from their origin in the Italian Renaissance. Flats with a frame that places the width of the lumber parallel to the face are called "Broadway" or "stage" flats. Hard-covered flats with a frame that is perpendicular to the paint surface are referred to as "Hollywood" or "studio" flats.
Usually flats are built in standard sizes of 8 feet (2.4 m), 10 feet (3.0 m), or 12 feet (3.7 m) tall so that walls or other scenery may easily be constructed, and so that flats may be stored and reused for subsequent productions.
Often affixed to battens flown in from the fly tower or loft for the scenes in which they are used, they may also be stored at the sides of the stage, called wings, and braced to the floor when in use for an entire performance.
Rails (or plates) are the top and bottom framing members of a flat. Rails run the full width of the flat (4 feet or 1.2 metres, for a 4 by 8 feet or 1.2 by 2.4 metres, flat).
Stiles (or studs) are the vertical members of the frame. The length of the stiles is the full height of the flat, minus the combined width of the rails (7 feet 7 inches or 2.31 metres, for a 4 by 8 feet or 1.2 by 2.4 metres, flat constructed of 2 1⁄2-inch or 64-millimetre, rails).
Toggles are horizontal cross pieces that run between the stiles or studs. The number and placement of toggles depends on the type of flat. The length of the toggles is the total width of the flat minus the combined width of the stiles (3 feet 7 inches or 1.09 metres, for a 4 by 8 feet or 1.2 by 2.4 metres, soft-cover flat constructed of 2 1⁄2 inches or 64 millimetres, stiles).
Corner blocks are used to join the corners of a soft-cover flat. They are normally made of 1⁄4-inch (6.4 mm) plywood, and are triangles with corners of 45°, 45°, and 90°. They are most often made by ripping the plywood at 6 1⁄2 inches (170 mm) and then mitering it at 45 degree angles to create triangles with 9-inch (230 mm) legs.
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