Abutterfly roof (sometimes called aV roof) is a form ofroof characterised by an inversion of a standard roof form, with two roof surfaces sloping down from opposing edges to a valley near the middle of the roof.[1] It is so called because its shape resembles abutterfly's wings.[2]
The modern butterfly roof is commonly credited to be the creation ofWilliam Krisel and Dan Palmer in the late 1950s inPalm Springs, California. It has been estimated that starting in 1957, they created nearly 2,000 houses in a series of developments that were popularly known as the Alexander Tract, which has been described by historian Alan Hess as "the largest Modernist housing subdivision in theUnited States."[2] Krisel confirms that while his work popularized the form, he was not its originator.[2]
The timeline of the emergence of the butterfly roof:[3]
Butterfly roofs are commonly associated in the US with 20th centurymid-century modern architecture. They were also commonly used in Georgian and Victorianterraced house architecture of British cities, where they are alternatively termed "London" roofs.[citation needed]
The form has no gutter as rainwater can run off the roof in no more than two locations, at either end of the valley, often into ascupper ordownspout. The form may be symmetrical, with the valley located in the center, or asymmetrical with an off-center valley.[4] The valley itself may be flat, with a centralroof cricket diverting water towards the valley ends, or sloping if the entire roof form is tilted towards one end of the valley.
The roof also allows for higher perimeter walls, withclerestory windows allowing light penetration without impacting privacy.[3]
A large house with a butterfly roof features prominently in the 2009 British TV crime drama trilogyRed Riding as 'Shangri-La', the home of corrupt property developer John Dawson, played bySean Bean.
| Roof shapes |  | |
|---|---|---|
| Roof elements | ||
.jpg)
