Blueprints really were blue
For the best part of a century, copying a large technical drawing meant a chemical process invented in the 1840s that produced crisp white lines on a deep blue background. It was cheap, hard-wearing and completely blue, and the drawings took their name from the colour.
Nobody has produced one that way since the 1950s. Plans are printed now, or increasingly never printed at all and carried round the SITE on a tablet — and everybody still calls the drawing a BLUEPRINT.
The order is the job
Foundations before walls, walls before roof, pipes and cables before the PLASTERER covers everything up. Get the sequence wrong and somebody has to break into finished work, which is expensive and makes enemies on both sides.
Managing that sequence is what a FOREMAN actually does: stopping six trades from needing the same room on the same morning, and making sure the GLAZIER does not turn up before the window frames exist. Planners map the whole job as a chain of dependencies and hunt for the longest path through it, because that path is the shortest time the building can possibly take.
The tree on the roof
When a new building reaches its highest point, many crews still hold a topping-out ceremony and fix a tree, a branch or a flag to the top of it. The custom is Scandinavian and very old, thought to be either an apology to the spirits of the trees felled for the timber or a blessing on the people who will live there.
It survives on towers of steel and concrete containing no timber whatsoever. Watch the top of any large building going up and eventually something green appears where nothing green has any business being.
Measuring beats guessing
A SURVEYOR sets the building out before anyone digs. Modern instruments bounce a laser off a target and record angles and distances to within a couple of millimetres, tied into satellite positioning, so the corner of the building ends up exactly where the drawing says it should.
Everything afterwards depends on that. A wall a few centimetres out on the ground floor becomes a serious problem twenty storeys up, so the ENGINEER and the INSPECTOR check work as it happens rather than admiring it at the end.
Concrete gets the same treatment. Samples are taken from loads arriving on SITE, kept in a laboratory and crushed after a set number of days to confirm they reached the strength the design assumed. Nobody wants to discover otherwise once the building is on top of it.
Architect or engineer?
The words get used interchangeably and they are different jobs. The ARCHITECT decides what the building is: how it looks, how people move through it, where the daylight lands. The ENGINEER works out what holds it up, and whether the architect's idea can be built without any of it arriving in the street below.
Both then defer to the person actually holding the TROWEL. A design that cannot be built by real people, in real weather, standing on a real LADDER, is not a building — it is a picture of one.