People in construction do not know how to read plans.

People in construction do not know how to read plans. Neither do those that draw, nor those that interpret drawings.

An unfair generalisation? Unconvinced? Orthogonal projection is the base of most construction related graphical documentation. It is performed every time a plan, elevation, section or detail is drawn or interpreted; What are the most important rules of this technique? Here are 3 questions:

1/ What is an orthogonal projection?

2/ Why has orthogonal projection become so popular in construction?

3/ How many views are needed to adequately describe a spatial element?

Why are the answers to these questions important? Because a technique that performed well for a number-of-hundreds of years has become an exercise that lost its meaning. Nowadays, most technical construction drawings come with a tag “do not scale”!

How is this related to BIM? We need to acknowledge that it is supposed to replace a well balanced system of tools, processes and a knowledge framework that existed for a long time. Unfortunately, the system disappeared. Construction people stopped learning what orthogonal projections meant, and what basic rules they must follow to use it. Then the processes disappeared followed by the knowledge framework; All three got replaced by flatcad; What is flatcad? My definition will be coming soon, before that, I’ll give you answers to my 3 questions noted today, tomorrow.