Wind brace
Wind Braces, in architecture, are diagonal braces to tie the rafters of a roof together and prevent racking. In the better sort of medieval roofs they are arched, and run from the principal rafters to catch the purlins.
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Wikipedia
Wind Braces, in architecture, are diagonal braces to tie the rafters of a roof together and prevent racking. In the better sort of medieval roofs they are arched, and run from the principal rafters to catch the purlins.