A curtain wall rarely fails at the centre of a typical module. Problems emerge at boundaries where material, geometry or responsibility changes. Curtain-wall engineering should therefore begin with interfaces, not only with the standard section.
1. Connection to the primary structure
Anchors must transfer calculated loads, accommodate concrete or steel tolerances and provide the required adjustment. Their positions need coordination before concrete pours or slab-edge completion. A small geometric deviation can otherwise create a major site intervention.
2. Movement and joints
The structure moves under load, temperature, shrinkage, creep and seismic action. The façade must accommodate relative movement without imposing unwanted forces on glass, seals or fixings. Joints need sufficient working range and continuity across the air and water lines.
3. Drainage and pressure equalisation
Water management does not rely on one external silicone line. Most curtain walls use controlled cavities, pressure equalisation and drainage paths. Every splice, corner, head and sill must maintain system continuity and discharge water to the exterior.
4. Glazing and glass support
Thickness, heat treatment, laminates, coatings and edge clearances relate to actual dimensions and loads. Setting blocks, glass bite, structural silicone and mechanical retention must match the specified build-up. Future glass replacement should also be possible without unrealistic access assumptions.
5. Perimeter fire barrier
The perimeter fire barrier is a separate but connected system. Continuity, compression, supports and compatibility with façade movement must be checked. Spandrel zones, sills and opaque panels require coordination with the overall fire strategy.
6. Adjacent materials and finishes
Roofs, parapets, walls, internal partitions, ceilings and floors all meet the curtain wall. Every junction must define how the air barrier continues, where waterproofing returns, who closes the fire stopping and which trade accommodates each tolerance.
The technical quality of a façade lies in the continuity of its layers and responsibilities. When every interface has an owner, detail, tolerance and inspection method, architectural intent can reach the completed building without hidden gaps.