While there is an emphasis on the use of 3D modeling and architectural BIM modeling for architectural design projects, the proven practice of using architectural designs and technical 2D drawings is still common in the AEC industry. Architectural drawing has evolved from the drawing board to computer-aided design and drawing programs (CAD). Siting practices help to provide architectural construction drawings that contain the technical details of architectural, structural and electrical elements required for the construction of a building. Understanding the stage in which architectural design takes place requires consideration of the workflow of a building’s life cycle.
The basic workflow of an architectural design project starts with the architect creating a conceptual plan that is usually modeled in 3D architectural models and displayed as photo-realistic images for marketing and presentation to clients and clients.
After the conceptual design has been approved by the client, the design is further elaborated and shared with other parties such as constructors and MEP engineers. The way the design for the ‘design development phase’ is developed by an architect lends itself to two options, either to develop a 3D model with more detail and then create subsequent sheets and details using a 3D tool such as Revit or AutoCAD, or as is still common, to develop the concept design in 2D using more traditional methods. From the conceptual plans of architects and engineers, a draftsman can convert these designs with CAD software programs to create technical drawings.
Architectural drafting is the process of creating engineering drawings that contain the floor plan, sections, views, detailed drawings and other documents in a construction drawing set (CD set) that are typically required for the construction of a building.
The difference between architectural drafting and modeling
Architectural drafting refers to the creation of technical 2D drawings and architectural construction drawings that are mainly used by contractors and consultants on site. Architectural 3D modeling refers to creating 3D models and displaying photorealistic images mainly used to present the architectural design for marketing purposes and then moving from there to create the technical 2D drawings basically feeling like an additional stage (the 3D modeling element). The main software used for drafting, to create 2D engineering drawings, is AutoCAD, while modellers use Revit and ArchiCAD to create 3D models and rendered images. Architectural draftsmen must have basic knowledge of 2D and 3D software such as AutoCAD and knowledge of engineering codes and design guidelines specified by organizations such as American National Standards Institute (ANSI), American Society of Mechanical Engineers (ASME), American Design Drafting Association (ADDA) , Public Works Government Services Canada (PWGSC), National Institute of Building Sciences (NIBS), BSI British Standards Institute and Standards Australia Code AS1100. Architectural modelers should have a deeper understanding of architectural, building and construction concepts and experience with 3D software programs such as Revit and ArchiCAD.
Why architectural drafting is still common in architectural design practices
Architectural 3D models are preferred by architects and designers as they provide a 3D perspective of the building’s conceptual plan; it simplifies project data management and allows design changes on the go. However, construction companies who need technical specifications of the architectural project prefer 2D engineering drawings and architectural construction drawings because they provide accurate details required for construction, most of the resources involved in construction understand 2D drawings, there are no software compatibility issues compared when using 3D models and it is a suitable solution to meet the budgetary requirements of a construction project. Some of the reasons why architectural designs are preferred by different construction companies are:
• Suitable according to building requirements – In some construction projects, 2D engineering drawings or architectural CAD drawings are sufficient to complete construction, without requiring additional information provided by 3D models. A construction drawing set (CD-set) contains all the plans, views, sections and detail drawings necessary for the construction. Technical codes, symbols and other additional information, such as the type of material, are given in technical drawings. That is why construction companies find 2D technical drawings sufficient to successfully complete construction.
• Availability of technical resources – Not all companies have the technical resources to provide 3D models. While drawing teams are qualified to work on AutoCAD to provide 2D engineering drawings, they may not be qualified to work on Revit to provide 3D models. In the construction industry, the availability of drawing teams that can provide technical 2D drawings is ample compared to companies providing 3D modeling services.
• Availability of software – The adoption of new software and practices has been gradual and slow in the construction industry. The software used in construction projects varies from country to country. Some countries use ArchiCAD and AutoCAD Architecture instead of Revit, which leads to incompatibility of project data. 2D technical drawings in AutoCAD are widely used and compatible, making it a preferred option for Revit 3D models.
• Suitable according to cost and budgetary requirements – In most cases construction companies do not find the need to invest more in 3D models, when drafting solutions you provide detailed technical drawings that are sufficient and relevant enough for construction. There is also an additional investment in resources skilled enough to understand and implement architectural 3D models on site.
While architectural 3D modeling and BIM modeling provides design-related information typically required by architects and designers at the design stage of a construction project’s life cycle, architectural drafting yields technical drawings that are not only about aesthetics but also high-quality detailing of construction elements. Architectural CAD drawings specifically communicate design intent and aid in the construction of buildings that businesses find relatively adequate over 3D models. Even as construction companies will eventually have to evolve towards combining the use of technical 2D drawings and architectural 3D models until then, the proven practice of using architectural drawing and drawing solutions in construction is indispensable.