Technical Booklet D Structure·Page 81·4C.36
Internal load bearing masonry walls
Internal loadbearing masonry walls must meet minimum thickness requirements as determined by equation, except walls in the lowest storey of a 3-storey building carrying upper-storey loads, which must be at least 140 mm or the calculated thickness, whichever is greater.
Internal loadbearing masonry walls should have a thickness not less than – except for a wall in the lowest storey of a 3 storey building, carrying load from both upper storeys, which should have a thickness as determined by the above equation or 140 mm, whichever is the greater.
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