Structure: Approved Document A

O N L I N E V E R S I O N A1/2 THICKNESS OF WALLS IN CERTAIN SMALL BUILDINGS Diagram 19 Lateral restraint at roof level See para 2C38 Walls which do not contain a major opening (iv) Horizontal lateral restraint at roof level but exceed 2.5m in length or height should be Walls should be tied horizontally at no more than bonded or tied to piers for their full height at not 2m centres to the roof structure at eaves level, more than 3m centres as shown in Diagram 18a. base of gables and along roof slopes as shown Walls which contain one or two major openings in Diagram 19 with straps fixed in accordance should in addition have piers as shown in with paragraphs 2C35 and 2C36. Where Diagrams 18b and 18c. Where ties are used straps cannot pass through a wall they should to connect piers to walls they should be flat, be adequately secured to the masonry using 20mm x 3mm in cross section, be in stainless suitable fixings. Isolated columns should also steel in accordance with paragraph 2C19, be be tied to the roof structure (see Diagram 19). placed in pairs and be spaced at not more than 300mm centre vertically. Structure Approved Document A 34 O N L I N E V E R S I O N