TRADITIONAL METHODOLOGY VS. BIM METHODOLOGY
The methods and processes that have traditionally been used for the elaboration of construction projects have always had several handicaps that are currently being solved with the evolution of the BIM methodology. By dividing the processes into their dimensions, we can compare both methodologies through 2D (planes), 3D (visualization), and 4D and 5D (measurements and budgets).
The traditional methodology focuses the project in a unitary way in its reference, but in a completely detached way in terms of processes and a single database.
With this methodology, 2D has to be drawn plane by plane. That is, if for a housing project we need three floor plans, eight sections, and four elevations, we must draw each one of them one by one. These plans are referenced to the same project, that is evident, but they are not directly connected neither between them nor the project, which basically means that any changes or modifications that are made in the project, must be done individually in all planes.
To obtain visualizations in 3D, you must use a model, or, in the last decade, a virtual model. However, although this model allows us to visualize the project volumetrically, in addition to its materials, this model does not contain any information of the elements that compose it, beyond the pure geometry. With the 3D model the same problem as in 2D planes appears: it is not interconnected with the rest of the project more than by reference, so that each change in the project, besides having to do it in each plane, it is necessary to modify it also independently In 3D.
Measurements and budgets are also done by hand, obtaining measurements of all surfaces, floors, etc., of the project, to incorporate them into a budget by applying unit prices. We again are faced with the same problem when using this methodology: any modifications need to be manually updated in the budget. If, for example, two windows are deleted, we will have to modify the budget and delete those two windows manually.
All this independence between processes has meant that much of the time and effort devoted to a project has had to be concentrated in production. Currently, the BIM methodology gives us a new vision and a new way of approaching the project processing. Among many other advantages, the main one is the unification of all aspects of the project in a single database, from which all the information is extracted.
This database is the BIM model. Differing from the traditional method, the BIM system is based on the creation of a central model, which consists of an exact virtual recreation of the building to be constructed, from which all the production and extraction of information necessary for the project stems.
In the BIM methodology all production is automated. The 2D planes are directly extracted from the model, through the definition of plants, sections and elevations that will be required, and directly linked to it, so that the changes that are entered in the model are automatically updated automatically in all planes .
The 3D visualization is another great advantage that is also in direct relationship with the central model. Since the BIM model contains all the information of each of the elements of the project, it will contain all the information related to the materials out of which it is built, as well. Thus, 3D visualizations would also be automated if modifications of materials are made, as well as containing all the physical information of the materials, which leads to a virtual representation that is closer to reality. BIM softwares are incorporating increasingly better visualization methods, evolving from traditional static rendering to current virtual tours and 360-degree visualizations.
The measurements are directly based on the information contained in each of the elements of the project. The software automatically extracts from the model the measurement of all of them, obtaining not only their geometric measurement, but also their identification and quantification. The price can be applied directly in the model itself, which also makes the budget updating easier.
The greatest advantage that the BIM methodology gives us in comparison to the traditional one, apart from a greater control of the project and all its constituting parts, is the release of a tedious work of information production and repetition of processes, automating the production and allowing for more time dedicated to the design phase, resulting in projects of higher quality, with less errors, deviations and problems in its construction.