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 16 Lateral support at roof level See para 2C36 Interruption of lateral support Small single-storey non-residential 2C37 Where an opening in a floor or roof for a buildings and annexes stairway or the like adjoins a supported wall and interrupts the continuity of lateral support, the 2C38 Size and proportion following conditions should be satisfied for the i. General purposes of Section 2C: The guidance given applies in the following a. the maximum permitted length of the opening circumstances: is to be 3m, measured parallel to the supported wall, and a. The floor area of the building or annexe does not exceed 36m². b. where a connection is provided by means other than by anchor, this should be provided b. The walls are solidly constructed in brickwork throughout the length of each portion of the or blockwork using materials which comply wall situated on each side of the opening, and with paragraphs 2C19 to 2C22. c. where a connection is provided by mild steel c. Where the floor area of the building or annexe anchors, these should be spaced closer than exceeds 10m² the walls have a mass of not 2m on each side of the opening to provide less than 130kg/m². the same number of anchors as if there were Note: There is no surface mass limitation no opening, and recommended for floor areas of 10m² or less. d. there should be no other interruption of d. Access to the roof is only for the purposes of lateral support. maintenance and repair. e. The only lateral loads are wind loads. Approved Document A Structure O N L I N E V E R S I O N 31