The predominant usage of the building is defined by the function with the largest share in the total gross floor area. The usage of the first above-ground floor then shows its main function, or the most common combination of two functions (if they each occupy roughly half of the floor area).

The result is two types of depiction of the functional structure of the city, which differ mainly in the intensity of the direct relationship to the surrounding public space. While information on the predominant usage of a building is essential for the assessment of the overall gross floor area statistics, the usage of the first floor is crucial for the assessment of the parterre, which is part of the public space of streets and squares.

The ability to display the predominant usage is thus suitable for analyses of the functional structure of the city, city districts or blocks, which are the basis for evaluating the potential and preferred use of development sites. Knowing the usage of the first floor makes it possible to identify basic spatial patterns of civic amenities, such as city streets with a commercial parterre (shops, services), the attractiveness of the parterre of residential areas, or areas without a typical parterre (e.g. campuses).

Data on the physical structure of buildings are valuable both for calculating the gross floor area and evaluating the volumes and areas of existing buildings, as well as for evaluating the urban structure and creating 3D visualisations of the city.

Analyses of the “roof” landscape and the number of floors are essential especially for setting the height zoning of the city or assessing the suitability of individual construction plans in terms of the relationship to the nature of the surrounding buildings. Information about the type of roof and the number of floors can be further used to refine the city’s 3D model.

To determine the height of a building, it is possible to use an approach that allows you to identify the absolute heights of selected segments or edges of individual buildings. Unlike the number of floors, this method uses the focus of individual objects in space in combination with a digital terrain model and digital surface model.

The height of the buildings, specifically the height of the outer edges, was used to characterise the height urban structure. In the vast majority of cases, the outer edges of buildings represent the eaves of buildings. The resulting lines on the buildings are thus defined as outer edges.

A digital terrain model and digital surface model (developed by TOPGIS in 2019) were used to obtain data on the height of the outer edges. The lowest altitude on the line was taken from the digital terrain model, whereas the maximum altitude was taken from the digital surface model. The relative height of the outer edges was calculated from the difference in values. The relative height calculated in this way has its limitations and may not correspond to reality, especially in areas where there is greenery near the buildings, which exceeds the height of the buildings.

The relative height of the outer edges is a basic set of data that is used in the practice of spatial planning. The eaves segment with the given heights serves as the basis for evaluating the height urban structure of the city. The data are used in the Planning analytical materials of the city of Brno, allowing them to be used, for example, to evaluate the relationship between the height of buildings, urban structure and population density or describe the perceived landscape scene.

From a spatial point of view, the building height structure corresponds to the historical development of the city. Higher buildings are concentrated in the area of the organic urban forms, i.e. the historic centre and the inner city centre. This area is followed by the wider centre, where the block structure is less clear (mix of apartment buildings and single-family houses) and there the height of buildings is mostly reduced.

Areas with a concentration of high-rise development are typical for housing estates arising in the period of complex housing construction (e.g. Bohunice, Starý and Nový Lískovec, Lesná, Bystrc, Vinohrady, Líšeň). Nowadays, a typical image of the city’s height structure is created mostly by the local occurrences of prefabricated apartment buildings surrounding the compact urban forms of the wider centre.

Low-rise buildings are concentrated mainly in residential (e.g. Žlutý kopec, Černá Pole) and the original working-class districts of the wider centre (e.g. Židenice) and also in peripherally located, formerly rural, settlements that were joined to Brno (e.g. Bosonohy, Tuřany, Líšeň, Soběšice). From the beginning, the low-rise character of suburbanisation in the outskirts of the city was gradually supplemented by medium-high construction of apartment buildings (e.g. Bystrc – Kamechy, Panorama; Slatina – Kigginsova; Královo Pole – Sadová; Medlánky – V Újezdech).