Cruck

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Cruck framing, Leigh Court Barn, Worcester, England Cruck framing.jpg
Cruck framing, Leigh Court Barn, Worcester, England
The Moirlanich Longhouse, a byre dwelling with a cruck frame Morlanich Longhouse 2004.jpg
The Moirlanich Longhouse, a byre dwelling with a cruck frame

A cruck or crook frame is a curved timber, one of a pair, which support the roof of a building, historically used in England and Wales. 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).

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Etymology

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.

Use

A half timbered house in Worcestershire framed with a full cruck Cruck cottage in Wick - geograph.org.uk - 742651.jpg
A half timbered house in Worcestershire framed with a full cruck

Crucks were chiefly used in the medieval period for structures such as houses and large tithe barns, which were entirely timber-framed. They were also often used for the roofs of stone-walled buildings such as churches. However, these bent timbers were comparatively rare, as they were also in high demand for the shipbuilding 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 Cecil Hewett, an authority on English Historic Carpentry, has stated that these 16th-century crucks are original.

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.

An example of a Yorkshire cruck barn complete with a heather-thatched roof can be found in Appletreewick. [1] The crucks or cruck "blades" are a single oak tree riven (split) in two to form an equally shaped A frame.

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] No cruck frames are known to have been built in North America though there are rare examples of what may be an upper cruck or knee rafters.

History

The oldest surviving crucks with dates confirmed by tree ring analysis date from around the middle of the 13th century. [4] They may have declined due to providing an inconveniently shaped space in cases where an upper floor was used. [5]

Revival

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. [6]

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.

Types

A jointed cruck St. Michael's Church Baddiley - geograph.org.uk - 272728.jpg
A jointed 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". [7]
  2. Base cruck: The tops of the blades are truncated by the first transverse member such as by a tie beam. [7]
  3. Raised cruck: The blades land on masonry wall and extend to ridge. [7]
  4. Middle cruck: The blades land on masonry wall and are truncated by collar beam. [7]
  5. Upper cruck: The blades land on tie beam, very similar to knee rafters. [7]
  6. Jointed cruck: The blades made from two pieces joined near eaves. They can be joined in at least five ways. [8]

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. [8]

See also

Related Research Articles

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<span class="mw-page-title-main">Great House Barn</span> Barn in Lancashire, England

<span class="mw-page-title-main">Rivington Hall Barn</span> Barn in Lancashire, England

Rivington Hall Barn adjoins Rivington Hall in Rivington, Lancashire, near Chorley and Bolton. The Tithe barn foundation stones support a Medieval cruck construction and possibly date to the between the 9th and 15th centuries. The structure was restored, altered and enlarged in 1905 by Jonathan Simpson for Lord Leverhulme. It is a Grade II Listed building.

A post is a main vertical or leaning support in a structure similar to a column or pillar, the term post generally refers to a timber but may be metal or stone. A stud in wooden or metal building construction is similar but lighter duty than a post and a strut may be similar to a stud or act as a brace. In the U.K. a strut may be very similar to a post but not carry a beam. In wood construction posts normally land on a sill, but in rare types of buildings the post may continue through to the foundation called an interrupted sill or into the ground called earthfast, post in ground, or posthole construction. A post is also a fundamental element in a fence. The terms "jack" and "cripple" are used with shortened studs and rafters but not posts, except in the specialized vocabulary of shoring.

<span class="mw-page-title-main">American historic carpentry</span>

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<span class="mw-page-title-main">Ty Coch Cruck Barn, Llangynhafal, Denbighshire</span> Building in Wales, UK

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<span class="mw-page-title-main">Minworth Greaves</span> Medieval hall house in Birmingham, England

Minworth Greaves is a timber cruck-framed, Grade II listed building in Bournville, an area of Birmingham, England. It is thought to date from the 14th-century or earlier, possibly as early as 1250. It is owned by the Bournville Village Trust. Minworth Greaves is situated next to Selly Manor, and is run as part of Selly Manor Museum. It was originally built in Minworth, near Sutton Coldfield to the North of Birmingham. After falling into extreme disrepair, it was purchased by George Cadbury and re-built by Laurence Cadbury in 1932 in the grounds of Selly Manor.

References

  1. "Craven Cruck Barn". Archived from the original on 2013-02-15. Retrieved 2013-01-06.
  2. Alcock, Nat (June 5, 2011). "The Significance of the Cruck Construction at Néchin, Belgium". L'architecture vernaculaire.
  3. "La charpente à cruck" (in French).
  4. Roberts, Edward (2003). "True Crucks and Related Frames". Hampshire Houses 1250-1700: Their Dating and Development. Hampshire County Council. p. 20. ISBN   1859756336.
  5. Roberts, Edward (2003). "True Crucks and Related Frames". Hampshire Houses 1250-1700: Their Dating and Development. Hampshire County Council. p. 21. ISBN   1859756336.
  6. Ross, P.; Mettem, C.; Holloway, A. (2007). Green Oak in Construction. High Wycombe: TRADA Technology. pp. 8–9, 14, 57, 112–3. ISBN   978-1-900510-45-5.
  7. 1 2 3 4 5 Brown, R. J. (1997) [1986]. Timber-framed buildings of England. London: R. Hale. pp. 66–67. ISBN   0709060920.
  8. 1 2 Brown, R. J. (1997) [1986]. Timber-framed buildings of England. London: R. Hale. p. 68. ISBN   0709060920.

Further reading