Formwork
CSI Division 03, Concrete
The temporary molds, built from wood, engineered panels, or steel, that hold freshly poured concrete in its designed shape and position until it cures enough to support itself, then get stripped away and often reused.
Why it matters
Formwork has to be strong enough to resist the substantial pressure of wet, unset concrete without bulging, leaking, or collapsing, and precise enough that the finished concrete comes out the exact size and shape the drawings call for; a formwork failure during a pour is one of the more dangerous jobsite incidents that can occur.
On a real project
A crew builds and braces plywood formwork for a foundation wall, checking it's plumb, square, and properly braced before the concrete pour begins, since any movement during the pour permanently distorts the finished wall.
Who this matters most to
A Carpenter builds and sets formwork, a skill distinct from finish carpentry that requires understanding the forces wet concrete will exert on it. A Superintendent inspects formwork bracing before authorizing a pour to proceed, since a formwork failure mid-pour can injure workers and ruin the concrete element entirely.
Where this goes wrong
A crew under schedule pressure skips a bracing step on a tall foundation wall's formwork, assuming it will hold for one pour. The formwork bulges under the pressure of the wet concrete partway through the pour, and the wall has to be demolished and re-poured once the compromised concrete cures out of shape.