The hammerbeam was developed to overcome the problem of spanning wide spaces by cantilevering the upper roof timbers from a beam projecting from the wall.
The late 14th-century roof of Westminster Hall is the most famous example, with hammerbeamsGlossary Term nearly 21 ft long introduced in place of the arcades which had previously divided the 11th-century hall, so that the building is roofed from wall to wall without intermediate supports. The hammerbeamsGlossary Term were often decoratedGlossary Term.
Elaborately carved hammerbeam roofs, sometimes in two tiers, became features of some of the grandest late medieval churches of East Anglia.
A distinctive phase of English Gothic which developed at the end of the 13th century and continued into the later 14th; sometimes abbreviated to Dec. Named from its elaborate window tracery, which abandoned the simple circular forms of Geometric in favour of more varied patterns based on segments of circles. Dec tracery makes much use of ogee or reversed curves, which were combined in the 14th century to produce reticulated and flowing tracery composed of trefoils, quatrefoils and dagger shapes. Similar inventiveness is seen in the patterns produced by the lierne and tierceron vaults of the period, in the three-dimensional handling of wall surfaces broken up by canopy work and sculpture and in imaginative spatial planning making use of diagonal axes.
In a timber roof, horizontal brackets projecting at wall-plate level like an interrupted tie-beam; the inner ends carry hammerposts, vertical timbers which support a purlin (horizontal longitudinal timber) and are braced to a collar-beam above.
Last updated: Monday, 26th January 2009