Manpower

Trussed rafters are very light components and for this reason are generally easily handled by two men. Roof spans above 9 m and pitches above 35°, however, result in a very awkward frame to handle and additional assistance will be required. British Standard 5268: Part 3 clearly states that trussed rafters forming girder trusses should be fabricated into their girder at the factory. This is now generally offered by the trussed rafter manufacturer to whom handling by fork trucks presents no problems, but once the girder arrives on site it may take six men to unload. The problem still remains of lifting the girder onto the building - clearly a crane should be considered to ensure safe handling of this large major structural component and to safeguard operatives from lifting excessive loads.

Similarly, the attic truss fabricated, generally from 47 mm timber and up to 3.9 m tall, presents problems; it is heavy and very unwieldy by virtue of its height. Cranes are, in the author's opinion, essential in handling large attics and attic girders, and delivery of the components should be organised with the manufacturer to ensure crane off-loading is available to lift the components, preferably directly onto the wall plates.

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