BIM vs CAD: main differences and real advantages

BIM vs CAD isn't a competition between 3D and 2D but two completely different processes. So what are the true advantages of BIM?

BIM vs CAD: What are the main differences? Let’s dive into a comparison to find out what process works better in a certain work contexts and why.

Many AEC professionals still use traditional 2D CAD technology for representing their design ideas to clients. This means that they still prefer to draw countless lines, polylines and generic geometrical shapes to represent their objects (doors, windows, walls, columns, etc) in the project's construction drawings, such as, floor plans, elevation views, cross-sections, etc.
This probably means that they still haven't come to grips with the enormous advantages of using BIM technology.
Thanks to 3D BIM, architectural design is accomplished by inserting graphical objects with their own functional characteristics and properties. These kind of intelligent objects allow the designer to produce detailed working drawings and construction documents automatically, avoiding to have to draw those incredibly complex drawings, full of lines and poly-lines all by hand.
So, let’s see the true advantages of using BIM technology.

from CAD to BIM

Differences between CAD and BIM

The difference between a CAD and a BIM is not simply in 3D modelling, but in a new way of understanding design procedures.

BIM allows to integrate useful information within the model at every stage of the design process, from the architectural to the executive, (structures, systems, safety, energy performance, etc.) and management (metric calculations, suppliers chain, maintenance etc.).

BIM is a collaborative and integration-based design method; the different actors involved can enrich the information model, insert, extract, update or modify information.

CAD and BIM are different mainly because BIM is a collaborative design environment.

CAD, or Computer-Aided Design, which allows the processing of a project through 2D and 3D drawings, it is limited to the design of simple graphic elements (lines, circles, arcs). It is not a collaborative method, although it allows the sharing of information through the exchange of drawings and diagrams.

BIM, on the other hand, is not limited to rendering, but specifies the performance and functions of each object.

Thanks to the BIM it is possible to recreate a virtual model of the building which is not only a three-dimensional representation, but a dynamic environment that contains a series of information on geometry, materials, load-bearing structures, systems, costs, safety, etc.

2D CAD vs 3D BIM: all the advantages of the BIM

There are multiple advantages working with the BIM methodology and therefore by using BIM oriented software, let’s see some of those which are almost universally recognized:

Time saving

The great efficiency of using a BIM software means that the designer can concentrate more on the creativity aspects of a project without having to constantly worry about updating a multitude of line entities throughout the entire project. This translates into an incredible increase in productivity because each object, chosen from a BIM objects menu, already comes with a set of pre-defined information that can provide useful data for calculating project cost, thermal performance aspects, maintenance, structural, etc.).
All this leads to a considerable saving of time.

Drastic reduction of Errors

Within a BIM design procedure, floor plans, elevation views and section views are simply different views of the same object. All views can be observed according to specific design phases. Whenever there's a change somewhere in the project, these changes seamlessly affect all other related documents.
As an example, by simply changing the external finish of a facade element, this causes a modification in the wall's transmittance value, its cost and even its structural load.
This allows the technician to avoid mistakes and be sure to have all drawings aligned with the latest project revisions wherever and whenever they are introduced.

Simplicity at its best

Thanks to the advancements of BIM technology, we can easily generate complex BIM models by transforming construction drawing resources from 2D to 3D models.
Architects can start to push their design capabilities even further proposing ideas that they wouldn't even have imagined doing using traditional 2D CAD tools.

Integration with other design aspects

BIM definitely expands design horizons. The 3D BIM model can in fact be enriched by a series of additional information that allow full integration with:
• structural calculation
• energy performance calculations
• construction estimating
• technical installations
• maintenance and facility management

3D BIM software

So ACCA has developed Edificius, a highly professional BIM software for architectural design with integrated structural design, energy performance, cost estimating, health and safety, maintenance and technical systems design, etc.
As a result in this video you'll be able to see how easy it was to recreate the 3D BIM model starting from a 2D CAD drawing of this modern building project in Spain (Zaragoza).

Click here to download Edificius, the architectural BIM design software