3D model of a Historic building: a case study with Edificius

How to create the 3D model of a Historic building: the example of “La Rotonda” by Palladio modelled in detail with a HBIM software

The possibility of applying Building Information Modelling (BIM) to support conservation and management of the built Heritage is today an interesting challenge in in the framework of 3D modelling and management/enhancement of historic buildings. In this blog article we’ll be taking a look at a practical case study that you could use as an example if you need to produce the 3D model of a Historic building and reproduce typical elements such as vaults, wooden ceilings, domes, etc.

As you can see in the image below, we’ve used the iconic  “La Rotonda” (or “Villa Capra”) by Palladio as a reference taking advantage of the HBIM environment commands in Edificius, the most advanced BIM technology applied to the restoration of existing and historic buildings and monuments.

The outcome was a BIM model where all its components (capitals, columns, vaults, windows, etc.) are intelligent parametric objects, rich in information that can be updated and implemented over time.

If you need to create a HBIM model of a historic building, start off by downloading Edificius for free and follow these tips below.

HBIM model produced with Edificius

All the steps to create the 3D model of a Historic building: a practical case study

The HBIM approach typically aims at developing BIM models from survey data “remotely sensed”. In fact, before starting the digitisation of a historical building (or more generally of an existing building) it is necessary to collect all the data and information useful to have a complete picture of the building of interest.

It is essential to collect information and geometric data (graphical elements, photos and documents of various kinds) for the construction of the model.

In the case in question, it was not possible to carry out a direct survey of the building. Therefore, I searched online for the various floor plans, elevation views and cross-sections. In addition, I collected a rich photographic documentation of the building.

In general, it is advisable to carry out a survey when possible to obtain geometric and material data on the site, using the most appropriate methods and available technologies:

• rulers, plumb levels and squares
• laser scanner
• TST (total station theodolite)
• photogrammetric survey
• etc.

Currently, the most suitable surveying practices involve the use of instruments such as laser scanners or cameras for terrestrial photogrammetry. So-called point clouds are thus obtained, containing information of geometric nature (their coordinates in a known reference system) and colorimetric nature, as each point is associated with a relative colour obtained from a photo taken by the instrument during scanning.

The survey accuracy and the information collected will affect the quality of the model.

Having gathered the necessary documentation, I started the modelling process with Edificius, the BIM software for architectural design.

First, I modelled the terrain of the current situation taking into account the differences in level, elevations and existing paths.

Digitalization of a historic building | Terrain modelling

Edificius has dedicated environment (Terrain Environment) where you can:

• import the terrain from Google Maps to automatically obtain the plot layout
• import a survey in DXF/DWG
• define contour lines, plans and elevation points
• model excavations and fills
• insert objects such as stairs, roads, yards, walls, vegetation, pools, flowerbeds, etc.

Switching back to the Architectural Environment, I set the building levels and sub-levels dimensions, obtaining the measurements from the collected information available.

HBIM model of a historic building | Levels setting

In order to model the structure, I imported the floor plans raster images and scaled the images. In this way, I used the floor plan image as a reference for modelling.

With Edificius you can also operate in different other ways. For example, you can:

• import drawings in DXF/DWG format and build the model using the automatic magic wand tool
• import the model IFC file to obtain an automatic objects recognition
• build the model by manually inserting the objects (walls, floors, windows, etc.) and the measurements obtained from the survey.

Next, I inserted walls, windows, doors, stairs and floors at each level using the corresponding parametric architectural objects and quickly defined the volume of the building.

The most substantial part of the modelling process was certainly creating the vaults and the decorations on the facades.

HBIM model of a historic building | Definition of volumes with parametric objects

At this point, I prepared the guidelines in plan view for the 3D creation of the vaults and their lunettes. Edificius has an editor in the HBIM environment that allows you to recreate the most common vault types and domes in historical buildings:

• barrel vault
• rampant barrel vault
• rampant half-barrel vault
• pavilion
• groin vault
• sail vault
• dome
• etc.

After the vaults, I modelled the roof, using the Roofobject. From the editor, I defined each individual slabs by setting slope lines and dimensions. I also modelled the double-pitched roof separately, covering the 4 pronaos that characterize the building fronts.

HBIM model of a historic building | The roof

I concluded the modelling of the horizontal elements by defining the wooden floors with the specific Edificius object and the large lowered dome covering the circular hall.

To model the capitals of the Ionic pronaos, the lesenes, the cornices and the other decorative elements of the facades, I used the Extrusion (solid)object.

For particularly complex elements, Edificius also enables the integration with the best solid modelling software currently on the market:

• SketchUp®
• Blender®
• Rhino/Grasshopper® .

It is also possible to import externally modelled objects or objects downloaded from the web in many formats (.3DS, .SKP, .OBJ, etc.). In my model example, I imported the statues on the 4 gables as a 3D object.

I completed the modelling by inserting the vegetation and assigning the materials.

3D HBIM model produced with Edificius

Once the modelling phase is over, it is possible to query the model to obtain or share information, automatically generate drawing models (floor plans, cross-sections, elevation views, etc.), renders, axonometric views, video presentations and explore the spaces in first person with Real Time Rendering or Virtual Reality.

(The new HBIM functionalities in Edificius are part of the BIM ReCult project co-financed by the European Union, the Italian State and the Campania Region in the framework of the POR Campania FESR 2014-2020)