Technical Booklet D Structure·Page 66·4C.9
Maximum length and height of wall
Unreinforced masonry walls must not exceed 12 m in length (measured from centre to centre of buttressing elements) or 12 m in height.
The wall should not exceed 12 m in length, measured from centre to centre of buttressing walls, piers or chimneys providing restraint, and not exceed 12 m in height.
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