Home » BIM and Professions » What is a Topographic Survey and why it is important

Topographic Survey

What is a Topographic Survey and why it is important

The importance of topographic survey in the design of buildings and infrastructure

Topographic surveying is an essential discipline in the fields of architecture and technical design as it provides fundamental data for the planning and implementation of architectural and infrastructural projects. Precision and quality of data play a decisive role in topographic surveying and the creation of topographic maps.

In this article, we will explore in detail the meaning and application of topographic surveying, highlighting its importance and utility. Today, with the use of new technologies, 3D terrain modeling software and specific cloud solutions, you can automatically extract elevation data and terrain textures with a simple selection on Google Maps® and create a detailed digital terrain model.

elevation data and terrain textures automatically from Google Maps®

elevation data and terrain textures automatically from Google Maps®

Topographic Survey: differences between planimetry and altimetry

Topographic surveying is a detailed graphic representation that combines two fundamental aspects: planimetry and altimetry.
Planimetry focuses on the horizontal dimensions of an area, such as the position of structures, roads, or buildings on a horizontal plane. Altimetry relates to the height or elevation of points relative to an altitude reference plane, such as sea level.

Topographic surveying is the art of combining these two pieces of information into a coherent and detailed representation, crucial in various fields, including architecture, civil engineering, and urban planning.

Role and importance of topographic survey in architecture

In architecture, topographic surveying is essential for the design of buildings and structures. It provides detailed information about the terrain’s conformation, enabling architects to adapt their designs to the site’s features. For example, when designing a house on hilly terrain, topographic surveying helps determine how to position the building optimally to maximize the view and minimize the effect of the slope.

Furthermore, topographic surveying is crucial for urban planning, allowing the assessment of the impact of new infrastructures, roads, or buildings on the surrounding environment.

Main applications of topographic surveying

Topographic surveying has a wide range of applications in the construction and building sector. It is used for designing buildings, roads, bridges, and infrastructure. Additionally, it is employed in road works to define the topographic course of roads, ensuring safe and easy navigation.

Common mistakes to avoid in topographic surveying

In the creation and interpretation of a topographic survey, it is important to avoid common mistakes that could compromise accuracy and effectiveness. Common errors include inaccuracies in data collection, failure to consider environmental factors, and lack of regular map updates.

How to interpret a topographic survey

To interpret a topographic survey correctly, it is essential to understand the different elements present on the map. Contour lines, for example, represent lines connecting points of equal elevation. The closer they are, the steeper the slope of the terrain. Conventional symbols indicate elements such as roads, watercourses, buildings, and points of interest. Acquiring skills in reading and interpreting this data is essential for making informed decisions based on the topographic survey.

Stages of topographic survey creation

The creation of a topographic survey involves several stages. Initially, accurate topographic surveys of the terrain are necessary, using tools such as theodolites, laser levels, GPS, and drones. Subsequently, the collected data is processed to create the topographic map, taking into account contour lines, control points, and structural elements. A critical step is the quality control phase, aiming to identify and correct any errors in the map. Accuracy is crucial to ensure the reliability of the topographic survey.

What is altimetric topography and why is it important

Altimetric surveying is a fundamental tool for understanding and working with our geographic environment. It provides detailed and precise data that directly influence the design, planning, and implementation of projects in the fields of architecture and civil engineering.
Topo-altitude surveying is a practice that allows obtaining detailed data on the topographic features of a specific geographic area, both in terms of planimetry (horizontal coordinates) and altitude (vertical coordinates). This data is then used to create a graphic representation of the earth’s surface, known as a topographic map or topography.

The topo-altitude surveying process involves the precise measurement of points of interest within the study area. These points may include variations in terrain, buildings, watercourses, roads, and other significant elements. Instruments used for the survey vary but often include theodolites, laser levels, GPS, and drones.

Each point is measured in terms of X, Y, and Z coordinates, representing its exact position both in plan and height relative to a predefined altitude reference system. Once all data is collected, it is processed through specialized software that allows creating a detailed topographic map. This map provides a comprehensive and accurate view of the terrain’s topographic features, including contour lines connecting points of equal elevation and other topographic elements.

Topo-altitude surveying is crucial in numerous contexts. For example, in architecture, it provides essential information to designers about the terrain’s conformation on which a building will be constructed, allowing them to adapt their designs optimally. In civil engineering, it is used for the design of road, hydraulic, and railway infrastructures, ensuring project safety and efficiency.

How to perform a altimetric topography with BIM software

Topo-altitude surveying is the key to precise and detailed design in the construction sector. With 3D terrain modeling software, you can create a Digital Terrain Model (DTM) easily and quickly, starting from surveys in different formats such as IFC, DWG, DXF, or even directly from Google Maps®. This way, you obtain a detailed and accurate DTM in no time. You can simulate excavation and backfill operations, compare different solutions and project levels, and integrate the model with landscape elements. Additionally, you have access to realistic 3D representations of the terrain through integrated rendering functions. You can also integrate the digital terrain model with landscape and built elements, making your design even more complete. Finally, you can automatically obtain all project documentation, detailed graphic tables, 3D representations, and the metric calculation of all operational phases.
If you need to perform an altimetric survey, try for free all the advantages of the 3D terrain modeling environment of Edificius!

What is a Digital Terrain Model (DTM)?

It is a 3D digital representation of the earth’s surface, including elevation data. These data can be collected from various sources, such as aerial photographs, satellite images, surveys in formats like IFC, DWG, and DXF, or directly from Google Maps®. Once processed, this data becomes a 3D model of the earth’s surface.

What is the difference between DTM, DSM, and DEM?

In short, the DTM represents only the earth’s surface, while the DSM includes everything covering it, such as vegetation and constructions. The DEM is a general elevation model that includes both the DTM and DSM.


In this video, you can see how to automatically obtain elevation data and textures from a simple selection on Google Maps® to quickly create the digital terrain model through the integration between BIM and Google Maps® of usBIM.land.