What is the difference between CAD and BIM?
Are CAD and BIM two worlds apart? What are the main advantages and limitations of CAD and BIM applications and can they coexist?
Professionals working in the areas of design and construction often face a dilemma: what software would best suit my needs, a Computer Aided Design software (CAD) or a Building Information Modeling software (BIM)?
The short answer is that, depending on the project you are working on, you would probably need both. A more accurate answer would require some considerations, starting from the differences between the two design tools.
What is CAD?
The acronym "CAD" stands for Computer-Aided Design. CAD software comes as a digital drawing tool, an advanced evolution of the drafting table used to create 2D or 3D designs, technical drawings and precise blueprints.
The ability to edit the drawing, add dimensions, tables and annotations allows the accurate creation of detailed designs, revisions and layouts for production and outputs.
What is BIM?
The acronym "BIM" stands for Building Information Modeling. BIM, differently from CAD, is not a digital drawing tool: it is a specialized modeling software to create a virtual version of a building that includes the geometry and also the spatial relationships, the functions, the geographic information and properties of building components.
Advantages of CAD and BIM
Both CAD and BIM offer specific advantages for the designer. Let's see what benefits an architect, engineer, or designer can gain from using either solution.
What are the benefits of CAD?
The benefits of CAD include precise dimensioning of the objects and detailed designs, easy editing and the ability to make revisions and add annotations. The smooth handling of layouts is a key feature of CAD: since the creation of blueprints is its natural purpose, this is one of the most considerable advantages of the using a CAD software.
In general, CAD applications give the designer more freedom to define the main idea and elaborate on it through progressive iterations. Also, CAD software produce high-quality drawings that closely follow the national drafting standards and it is often the most sensible choice for smaller to medium size projects. CAD is invaluable for engineering and architectural tasks where accuracy is of greatest importance.
What are the benefits of BIM?
The main advantage of BIM is in the "i" that stands for information. The various components and systems (structural, HVAC, plumbing, etc.) of the model contain associated information like material, physical properties and costs, and are updated in real-time. This added information leads to greater efficiency and cost control. The ability to keep quantities and costs under control is the main reason why large developments and public projects may actually require the use of a BIM software.
BIM allows designers to merge and integrate in one model the contributions of the various collaborators, from architects to engineers and contractors.
BIM also provides better visualization and simulation, helpful in making informed decisions throughout the building's lifecycle.
Finally, organizing a complex project with a BIM software is more effective compared to a CAD application, where all the drawings are arranged in a single model space.
Weaknesses of CAD and BIM
Both CAD and BIM software also have their own drawbacks and weaknesses. Let's see what the most common criticisms are.
The limitations of CAD
The most common limitation in a CAD package is the lack of information associated to the geometry: a project element, like a wall or a window, is just a block made of lines and hatches and the only properties that it can store are geometric properties and its layer's name. Also, changes do not automatically update connected elements and tables.
The main strength of a CAD package, that is the freedom it gives to the designer, can also become a weakness when managing a project made of many drawings can become difficult and the use of non-standard elements, that are not defined by a type, leads to reduced efficiency.
Drawbacks of BIM
BIM can be intimidating to learn and implement: it requires a significant investment in terms of both time and money. Keeping the model updated throughout the project's lifecycle can be challenging as it requires consistent input from all collaborators.
Also, being a modeling oriented software, the creation of accurate layouts could require the use of an external software because of the lack of evolved drafting and annotation tools for presentations.
Another point to consider is a certain feeling of being a prisoner of predefined templates because, when designing with libraries of standardized industrial components, you have to use all of your creativity to avoid the risk of making ordinary architecture.
Bridging the gap between CAD and BIM: HighDesign Pro.
What if you could get the best of both worlds? With HighDesign you can.
Since its first release HighDesign came as a different CAD application, bringing in some BIM concepts: multiple design spaces, called sheets, parametric design tools such as walls, doors and windows, and the ability to store properties and information.
HighDesign is a CAD application with all the advantages of modern drafting and annotation tools and the ability to create accurate layouts and effective presentations. At the same time, HighDesign offers many benefits of BIM applications:
- Organize the project through specialized sheets: drafting sheets, details, schedules, layouts, each with its scale and units.
- Design using parametric elements such as walls, columns, doors, windows that respond to input values and constraints.
- Associate information to the project and its design elements. The associated information can be extracted and visualized in annotations, tables, and interactive schedules.
Also, HighDesign encourages the use of styles and types so that each project element can be identified, computed and documented both as a single instance and as a class member. That means that modifying a type also modifies all the instances of that type in the project. At the same time, the use of styles and types is not enforced, so that the designer retains his or her freedom to create and think differently.
To learn more about the differences between HighDesign and other CAD apps, see the article "HighDesign vs AutoCAD LT: 4 Key Features That Set HighDesign Apart."
HighDesign is the powerful CAD and architectural design application to create, document, and publish 2D designs, built for architects, engineers and designers. For macOS and Windows.
Our mission at Ilexsoft is to make HighDesign the best solution for architects and designers.