The Masons' Loft has one of the finest surviving "scissor braced" timber roofs in the country. This roof is one of the five surviving medieval timber roofs of the Minster, along with the roof of the Chapter House, the South and North transept and the central tower (Hughes, 1955). There are a total of 43 trusses in the roof: 20 in the north-south range; 22 in the east-west range and a French truss which spans the junction of the two roofs (fig.1).
Fig.1: The French truss and north-south limb of the room.
During the spring of 2002, and in advance of essential timber repairs, the archaeological research undertaken by Kate Giles has concentrated on the timber roof. Through the detailed examination and recording of the trusses, it was discovered that some of the trusses carried carpenters' marks. The carpenters' marks were usually Roman numerals that helped to understand how the trusses fitted together when they would be erected. These marks were essential as in the medieval period timber-framed roofs were usually pre-fabricated off-site and then transported to their place of installation. The carpenters' marks of the Masons' Loft, though, do not relate to the sequence of the erection within the roof and not all of the trusses have them. That could be because many of the trusses are almost identical and so their position in the roof was of less significance. Another reason could be that the trusses may have been designed for the original roof of the vestibule, and then sat around waiting for the completion of the loft (Giles, 2002).
While archaeological research was undertaken in the roof, detailed CAD drawings were produced for each of the trusses. These were used as a primary archive for the model's roof (fig.2 and 3).
Fig.2: The model's French truss and east-west limb of the roof.
Fig.3: CAD drawing of the French truss.
Dendrochronology might shed further light on the date and structural sequence of the roof, but sadly Nottingham University Tree-ring Laboratory were unable to fit the samples of the trusses into one of the existing reference chronologies.
Page created 23 August 2002 by Vicky Sypsa
Last updated 30 august 2002
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