Building Technology parts G, Hand J of the Building Regulations. Mor~ det~iled reference will be made to many of these regulations In later chapters. Dimensional Co-ordination BS 4011 21 recommends that the first selection of basic sizes for the co-ordinating dimensions of components should be in the order of preference, n by 300 mm; n by 100 mm; n by 50 mm; and n by 25 mm, where n is equal to any natural number including unity. It is essential to relate components to a grid if they are to fit into the space planned for them within a building, without the need for trimming and cutting. Also, by using them in accordance with a grid, it will be poss!ble. to reduce the variety of components and increase standardisation and rationalisation in building. The grid lines can be based on the centre lines of walls and columns or on wall and column faces. Axial grids are most suitable for framed buildings and face grids are better suited for buildings with load-bearing walls. Key reference planes constitute load-bearing walls, columns and upper and lower surfaces of floors and roofs. The spaces between these key reference planes are termed controlling zones and the distances between these zones are called controlling dimensions. The recommended sizes of controlling dimensions are prescribed in BS 4330. 22 Intermediate key reference planes control the position of the heads and sills of windows and heads of door sets. of dimensions in building. Co-ordinating sizes for building components and assemblies 22. BS 4330: 1968 Recommendations for the co-ordination of dimensions in building. Controlling dimensions. PD 6444: Recommendations for the co-ordination of dimen- Front Matter....Pages i-xiv The Building Process and Siteworks....Pages 1-12 Building Drawing....Pages 13-23 Foundations....Pages 24-42 Walls....Pages 43-77 Fireplaces, Flues and Chimneys....Pages 78-88 Floors....Pages 89-111 Roofs....Pages 112-135 Windows....Pages 136-148 Doors....Pages 149-160 Stairs and Fittings....Pages 161-172 Finishings....Pages 173-183 Water Services and Sanitary Plumbing....Pages 184-198 Drainage....Pages 199-213 External Works....Pages 214-224 Building in Warm Climates....Pages 225-242 Back Matter....Pages 243-250
