Rafter – A sloping roof beam, usually from eve to ridge. In traditional timber framing the rafters share loads in common; a full-length intermediate rafter runs from eave to ridge but a jack rafter goes only part way, meeting with hip or valley rafters. The term ‘rafter’ is also applied to all types of trussed rafter, the sloping beam of a portal frame, and the principal rafter of a truss.
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