A Butterfly plan, also known as a Double Suntrap plan, is a type of architectural plan in which two or more wings of a house are constructed at an angle to the core, usually at approximately 45 degrees to the wall of the core building. It was used primarily in late Victorian architecture and during the early Arts and Crafts movement.
Victorian interest in the plan originated in the 1891 remodelling of Chesters, Northumberland, by Norman Shaw. To the original, square house of 1771 he added five wings; three of these were diagonal, creating suntrap flanks for the south and west fronts.
The principle of the butterfly plan was also re-adapted within an overall rectangular overall form, as for instance in Kallio Library in Helsinki, Finland, by architect Karl Hård af Segerstad, completed in 1902.
Notable Arts and Crafts examples:
- The Barn, Exmouth, Devon, by Edward Schroeder Prior (1897)
- Happisburgh Manor, Happisburgh, Norfolk, by Detmar Blow to a concept by Ernest Gimson (1900)
- Papillon Hall, Lubenham, Leicestershire, by Edwin Lutyens (1902–4, demolished in 1950)
- Home Place, Kelling, Norfolk, by Edward Schroeder Prior (1903–4)
- Kelling Hall, Kelling, Norfolk, by Edward Maufe (1913)
- Yaffle Hill, Broadstone, Dorset, by Edward Maufe (1930)
Kallio Library, Helsinki
- English Heritage Online thesaurus butterfly plan
- Beckett, Matthew (24 October 2012). "The Butterfly House". New architecture blog. Country Life. Retrieved 24 October 2015.
- Brooks, Alan; Pevsner, Nikolaus (2007). The Buildings of England: Worcestershire. New Haven: Yale University Press. pp. 653–56. ISBN 978-0-300-11298-6.
- Historic England. "Chesters (1155585)". National Heritage List for England (NHLE). Retrieved 24 October 2015.
- Historic England. "The Barn (1164569)". National Heritage List for England (NHLE). Retrieved 25 October 2015.
- Drury, Michael (2000), Wandering Architects: In Pursuit of the Arts and Crafts Ideal, Shaun Tyas. ISBN 190028913X
- Cantor, Leonard (1998), Historic Country Houses in Leicestershire and Rutland. Kairos Press. ISBN 1871344182
- Historic England. "Thornfield residential home for the elderly (1049826)". National Heritage List for England (NHLE). Retrieved 25 October 2015.
- Historic England. "Kelling Hall (1151974)". National Heritage List for England (NHLE). Retrieved 25 October 2015.
- Historic England. "Yaffle House and attached screen wall (1275360)". National Heritage List for England (NHLE). Retrieved 25 October 2015.