Both the BIM (Building Information Modeling) methodology and the various green building rating systems (e.g. WELL, LEED, BREEAM) have become part of the construction planning. Larger design offices already have a developed system for building information models, but the processing of certifications is not yet part of the BIM approach in practice. TSPC intended to fill this gap when, summarising its practical experience, it started to integrate the documentation of building classifications into its existing BIM standards. In our article this knowledge is presented through a schematic floor plan of an office building. It is important to note that at TSPC the processing is done with ArchiCAD software, so the solutions adopted are primarily, but not exclusively, ArchiCAD compatible.
The floor plan of the presented office building is on Figure 1. This sample project describes the procedure/methodology used to document multiple building classification credits. The floor plan consists of simple walls, doors and windows, zones and objects.
In order to make these elements valuable for a building classification system, specific properties need to be assigned. This can be done through the ArchiCAD property manager panel. The duration of the use of each room is required for many classification credits, therefore the methodology is presented through the implementation of their occupation. To do this, a new value set based property must be added in the property manager and assigned to the model elements classified as zones (Figure 2). The following four values are included in the value set:
Once the value set has been assigned to the zones and the corresponding values have been manually set, the visual and quantitative processing of the data can commence.
A new graphical override combinations must be created to visualize the values recorded. This can be done on the graphic override palette. For the set, we develop specific rules that override the appearance of the zones by referring to the properties created as described above (Figure 3). This makes it possible to distinguish the three categories (Figure 4).
The advantage of this method is that a given model element can appear in several different views with different graphics based on the assigned individual properties, thus avoiding multiplied processing (e.g. duplication, drawing, overriding element settings, etc.).
In addition to data visualization, it is usually necessary to prepare a statement for different building classification credits according to different criteria, which usually means a floor area or a cubic meter statement. These are made using ArchiCAD schedules. As with graphical overrides, it is necessary to create a rule, that shows the sum values of the zones, in this example the area (Figure 5). The existing individual value to be displayed must be set, so that the areas are listed according to this feature.
The list can be saved in excel format to do more complex calculations (for example, showing percentage data).
Another advantage of the listing function is that specialised data can be imported into the central model, thus creating a secure communication that loses no data. (Figure 7.)
In the example, electrical designers calculate the performance of the calculated consumers per room. Values are recorded in an XLSX format zone list exported from ArchiCAD using the “export property values” option. Once the data is recorded, these XLSX lists can be imported into ArchiCAD, and the software automatically assigns the performance values to the appropriate room (Figure 8). Additional characteristics can be calculated from the data obtained, for example, the Watt/m2 value of the rooms can be calculated. Automatic verification is also available on whether the value is appropriate.(complies with the ASHRAE 90.1 standard required by the LEED).
In view of the fact that reaching a green building classification requires a number of different credits, it is of certainly important that the tasks and workflows to be carried out can be carried out in an automated way. Changes in design can be automatically tracked or with minimal intervention with BIM-based developments. This can lead to significant reduction of human and mechanical resource in case of high credit numbers. Compliance with the target requirements can thus be achieved much more efficiently, more accurately and with less energy investment than with conventional documentation techniques.
Authors: Sándor Cseke, Dóra Szalai