Fenestration
What Is Architectural Fenestration?
Fenestration is the arrangement of openings in a building envelope — the windows, doors, curtain walls and glazed assemblies that admit light and air while separating inside from outside.
Fenestration is an assembly, not a product
A window is not a frame with glass in it. It is a frame system, a glazing build-up, gaskets, drainage paths, hardware and an anchoring detail, each of which affects how the assembly performs.
This is why performance documentation is issued per system and per configuration. Change the glass, the size or the hardware and the behaviour changes with it.
What fenestration has to resolve
Every glazed opening is asked to do several things at once, and the requirements pull against each other.
- —Thermal transfer between inside and outside
- —Solar gain, daylight and glare
- —Air infiltration and water penetration
- —Structural resistance to wind load
- —Acoustic separation
- —Safety, egress and security
Why it is specified early
Fenestration sets the opening dimensions, the structural tolerance and the interface with surrounding construction. Decided late, it becomes a set of compromises made on site.
Decided early, it coordinates with the structure, the interior detail and the mechanical strategy.