Above: Historic buildings in Nottingham, with a repetition of mansards and pitched roofs.
Below: This modern building applied a treatment that creates the appearance of smaller volumes with mansards and pitched roofs, in keeping with the geometry of the historic buildings in its setting (see image on the left). Gable ends give presence to the street but the mansards help reduce the overall mass and dominance of the building, as well as adding to the visual interest.
3. Geometry
The overall geometry of buildings is closely related to their function and the purpose of its various parts. However, there are times when designing purely with function in mind can lead to form and massings that do not sit comfortably in the site context, either because the massing is oversized or the proportions do not respond to neighbouring buildings. Feasibility studies for urban settings are always best approached with an outwards-in philosophy, confirming what type and size of the geometry is suitable to the site before attempting any other design strategy. Streetscapes often have geometries that repeat more than others. Buildings that contrast with the geometry tend to stand out, forming small landmarks that help people navigate the city. Geometry can be a strong design strategy but mimicking buildings that are the exception to the rule can have the adverse effect of undermining the prominence of unique historic buildings.
Modern commercial developments tend to have larger massings and volumes than buildings from historic periods. However, it is possible to manipulate the massing of new large buildings to achieve designs that sit comfortably within their historic settings. For example, façade treatments can make a large volume look slimmer, shorter or smaller than it actually is. A good way to do this is splitting façades vertically and working with rhythms.
Cities, streets and façades have a natural rhythm given by the repetition of their parts and their position in space. For example, equal windows with equal separation will have a monotone rhythm; but if the central windows are different in size these can act as an accent. Façades have a vertical and a horizontal rhythm. If the top floors have smaller windows than the lower floors, a variation is created in the vertical rhythm of the building.
Design Criteria
3.1 The geometry of the proposals is informed by the general urban context of the scheme and not solely led by function.
3.2 The geometry of the proposals is informed by the geometry and proportions of the immediate surrounding environment.
3.3 Proposals are formed by geometrical component parts that relate to each other in terms of size, position and separation, and that follow specific and clear design rules.