Steel Buildings in Europe

Part 2: Concept Design 2 - 24 4 ANATOMY OF BUILDING DESIGN The building design is dependent on various parameters:  Floor grid  Building height  Circulation and access space  Services requirements and service integration. These aspects are addressed as follows: 4.1 Floor grids Floor grids define the spacing of the columns in orthogonal directions, which are influenced by:  The planning grid (norm ally based on units of 300 mm but m ore typically multiples of 0,6, 1,2 or 1,5 m)  The colum n spacing along the façade, depend ing on th e façade m aterial (typically 5,4 m to 7,5 m)  The use of the internal space (i.e. for offices or open plan space)  The requirements for building service distribution (from the building core). Along the façade lin e, column spa cings are no rmally defined by the need to provide support to the cl adding system (for exam ple, a m aximum column spacing of 6 m is normally required for brickwork). This influences the column spacing internally, unless additional columns are used along the façade line. The span of the beam s across the building norm ally conforms to one of the following column grid arrangement:  Single internal line of colum ns, placed offset to the line of a central corridor. This is shown in Figure 4.1  Pairs of column lines on either side of a corridor  Column-free internal spans with columns located along the façade line. For naturally ventilated offices, a build ing width of 12 m to 15 m is typically used, which can be achieved by two spans of 6 m to 7,5 m. A single span can also be pro vided with deep (400 mm or more) precast concrete hollow core units spanning the full width of the build ing. Natural lighting also plays a role in choice of the width of floor plate. However, in m odern buildings, a long sp an solution provides a cons iderable enhancement in flexibility of layout. For air-conditioned offices, a clear span of 15 m to 18 m is often used. An exam ple of the colum n grid for a long span option in a building with a large atrium is shown in Figure 4.2.