World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0002035450
Reproduction Date:

Title: Cruck  
Author: World Heritage Encyclopedia
Language: English
Subject: Selly Manor, Wood products, Architecture of Scotland in the Middle Ages, Truss, Whirlow Hall Farm
Publisher: World Heritage Encyclopedia


Cruck Framing: Leigh Court Barn, Worcester, England.
The Moirlanich Longhouse, a blackhouse with a cruck frame.

A cruck or crook frame is a curved timber, one of a pair, which supports the roof of a building, used particularly in England. This type of timber framing consists of long, generally naturally curved, timber members that lean inwards and form the ridge of the roof. These posts are then generally secured by a horizontal beam which then forms an "A" shape. Several of these "crooks" are constructed on the ground and then lifted into position. They are then joined together by either solid walls or cross beams which aid in preventing racking (the action of each individual frame going out of square with the rest of the frame, and thus risking collapse).

The term crook or cruck comes from Middle English crok(e), from Old Norse krāka, meaning "hook". This is also the origin of the word "crooked", meaning bent, twisted or deformed, and also the crook used by shepherds and symbolically by bishops.

Crucks were chiefly in use in the medieval period for structures such as large tithe barns. However, these bent timbers were comparatively rare, as they were also in high demand for the ship building industry. Where naturally curved timbers were convenient and available, carpenters continued to use them at much later dates. For instance, base crucks are found in the roofs of the residential range of Staple Inn Buildings, Nos. 337 – 338, High Holborn, London. This is dated by documented records to 1586, with significant alterations in 1886 (under Alfred Waterhouse) and further restorations in 1936, and 1954–55. Despite these changes, an authority on English Historic Carpentry, Cecil Hewett, has stated that these 16th-century crucks are original.

During the current revival of green oak framing for new building work, which has occurred mainly since approximately 1980 in the UK, genuine cruck frames have quite often been included in traditionally carpentered structures.[1] There are also some fine, historically authentic reconstructions. For instance, Tithe Barn, Pilton, Glastonbury, whose original roof was destroyed by lightning, has been carefully rebuilt in 2005 from curved oaks. The necessary trees were sought out, using special templates, in English woodlands.

The large main barn of the manor house Barlow Woodseats Hall features what is claimed to be the longest continuously roofed cruck barn in Derbyshire, and possibly even in the United Kingdom.

No cruck frames are known to have been built in America though there are rare examples of what may be an upper cruck or knee rafters. Rare examples of cruck framing are found on continental Europe such as in Belgium,[2] Flanders, Northern France and the Corrèze region of France.[3]

An example of a Yorkshire cruck barn complete with a heather thatched roof can be found in Appletreewick.[4] The crucks or cruck "blades" are a single oak tree riven (split) in two to form an equally shaped A frame.

Types of crucks

A half timbered house in Worcestershire, GR SO961453, framed with a full cruck
  1. True cruck or full cruck: The blades, straight or curved, extend from a foundation near the ground to the ridge. A full cruck does not need a tie beam and may be called a "full cruck -open" or with a tie beam a "full cruck - closed".[5]
  2. Base cruck: The tops of the blades are truncated by the first transverse member such as by a tie beam.[5]
  3. Raised cruck: The blades land on masonry wall and extend to ridge.[5]
  4. Middle cruck: The blades land on masonry wall and are truncated by collar beam.[5]
  5. Upper cruck: The blades land on tie beam, very similar to knee rafters.[5] In Dutch called a kromstijlgebint.[6]
  6. Jointed cruck: The blades made from two pieces joined near eaves. They can be joined in at least five ways.[7]

The apex of a cruck frame also helps to define the style and region of the cruck. Different types include the butt apex, halved, housed, yoke, and crossed forms.[7]


  1. ^ Ross, P.; Mettem, C.; Holloway, A. (2007). Green Oak in Construction. High Wycombe: TRADA Technology. pp. 8–9, 14, 57, 112–3.  
  2. ^ Alcock, Nat (June 5, 2011). "The Significance of the Cruck Construction at Néchin, Belgium". L'architecture vernaculaire. tome 34-35 (2010-2011). 
  3. ^ "La charpente à cruck" (in French). 
  4. ^ Craven Cruck Barn
  5. ^ a b c d e Brown, R. J. (1997) [1986]. Timber-framed buildings of England. London: R. Hale. pp. 66–67.  
  6. ^ Herman Janse (1989). "Houten kappen in Nederland 1000-1940" (in Dutch). Retrieved January 4, 2013. 
  7. ^ a b Brown, R. J. (1997) [1986]. Timber-framed buildings of England. London: R. Hale. p. 68.  

Further reading

  • Hewett, Cecil A. (1980), English Historic Carpentry, Philimore, pp 231–233. ISBN 0-85033-354-7
  • Harris, Richard (1978), Discovering Timber-Framed Buildings, Shire Publications Ltd. Princes Risborough, Buckinghamshire. ISBN 0852634277
  • Alcock, N. W., Barley, M. W. et al (1996), Recording timber-framed buildings - An illustrated glossary, Council for British Archaeology, York. ISBN 1872414729

External links

A jointed cruck
  • Cruck database
  • Black and White Timber Framed houses
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.