Think of a BIM model as Middle Earth. Think of the paper set as The Lord of the Rings.
Building Information Modeling architects like myself dream of a paperless world. It is not the paperless dream of the 1990s. We are not interested in swapping one medium for another for reasons of storage or convenience. Not much is gained by going paperless using two-dimensional CAD programs. A Building Information Model, on the other hand, is a virtual representation of a building. The BIM walls have area, volume, materials and other attributes that can be queried. The line representation of that BIM wall in a paper print is just a pair of lines. If I give a BIM model to a contractor, they can see its richness and use it to create the actual building. If I give the contractor a set of drawings printed from that BIM model, all that richness is gone. BIM and paper drawings are at odds because printing a set of drawings from a BIM model destroys information. What is the role of paper sets in a BIM world?
Paper representations of buildings are going to be here for a long time. Why? Paper sets of drawings are almost indestructible. A paper set will last a lot longer on a job site than a BIM model on a laptop. A paper set of drawings is easy to understand. Flipping from one page to the next is easy, or at least easier than switching from one on-screen view to another. Buildings are easy to construct from well-formed paper sets of drawings. They have been for a long time. Paper is still the pre-eminent way to communicate a design.
Can BIM and paper drawings work to each other's mutual benefit?
The task of the designer is two-fold: to create the design, and then to communicate the design. BIM platforms excel in improving the way designers create. Think of the BIM model as an idea for a book. An author may have worked out the plot and the characters. She still needs to write the book. A well-developed set of paper drawings is a useful snapshot of the BIM model. In fact, it is the critical, culminating snapshot of the BIM model. A BIM model can be complete without being understandable or even accessible. The paper set is the communicating medium through which the designer conveys facts about the virtual model. Think of a BIM model as Middle Earth. Think of the paper set as The Lord of the Rings.
The problem remains that the typical paper set is series of shorthand diagrams, not a narration of the model. Paper drawings need to change. They need to reflect the fact that projects are being designed as virtual representations of actual buildings. They somehow need to preserve the rich information set contained in the electronic BIM model. They need to become the communicating medium that provides the narrative for understanding the model.
We create our paper sets to be reflections of the BIM model. For instance, BIM models use wall families. Each family has its unique set of materials and thicknesses. Each wall family can be identified with a unique type mark and instance mark. The same is true for ceilings, floors and roofs. Our drawing sets start off with a sheet documenting every wall, floor, ceiling and roof used in the project: legends of these assemblies (we do not use legends to do this. We use actual instances built in a future phase). Our plans and sections then use type tags to identify where these families are used in the model.
Each wall type used in the project is documented with material tags, dimensions and a type tag.
Wall sections are annotated using wall, ceiling, floor and roof type tags.
Architects are used to doing this for windows and doors. A sheet in the set graphically explains each type of door in the project. Plans and sections then identify a specific door’s location. Why not use this same system for casework, specialty equipment, furniture, signage: for every component in the entire project?
BIM models are obviously three-dimensional. Those three dimensions should show up on paper. Stairs can be explained in plan, section and elevation. How much easier it is to understand a stair in axonometric. We also organize our stairs by type: Stair Mark 1 and 2 might be Type A. Stair Mark 3 and 4 might be Type B. By referring to Stair Mark 4 as a Type B stair, we are taking advantage of BIM’s ability to create logical sets of elements.
In short, our paper drawings are documents that help explain how we built the BIM model. Through extensive use of schedules and legends, the drawing set explains the components used in the model and their quantity. It then uses these explanations to show where in the model these families are located. By describing components as members of a Type, we are using the logical ordering of the BIM model in the paper set.
BIM models are rich in data, but the richness is not easily communicated. A paper set of drawings put together with the goal of explaining and communicating the BIM model can serve as a useful medium superior to a traditional paper set.