Technical Booklet D Structure·Page 84·4C.43
Horizontal lateral restraint at roof level
Walls must be tied horizontally to the roof structure at eaves level, base of gables and along roof slopes at not more than 2 m centres using straps fixed in accordance with specified diagrams, with isolated columns also tied to the roof structure.
Walls should be tied horizontally at not more than 2 m centres to the roof structure at eaves level, base of gables and along roof slopes with straps fixed in accordance with Diagrams 4C.13 and 4C.17. Where straps cannot pass through a wall they should be adequately secured to the masonry using suitable fixings. Isolated columns should also be tied to the roof structure.
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