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In commercial Swiss structural steelwork, architectural metalwork, and curtain wall engineering, the fabrication of load-bearing steel and aluminum structures, balustrades, escape staircases, and unitised glazed façades requires strict alignment between structural analysis, safety standards, and factory quality assurance. Following the enactment of the Swiss Construction Products Act (BauPG), load-bearing metallic components may only be placed on the market accompanied by a valid Declaration of Performance (DoP) and Factory Production Control certification under EN 1090. Missing material 3.1 inspection certificates or expired welder qualifications result in handover rejections, site stoppages, and invalidated insurance coverage.

1. Statutory Construction Product Governance: Swiss BauPG, EN 1090 & Execution Classes (EXC)

Fabricating load-bearing metallic structures in Switzerland is governed by the Federal Act on Construction Products (BauPG, SR 933.0 ) and harmonized standards SN EN 1090-1 / -2 / -3 under the guidance of Metaltec Suisse (AM Suisse) :

  • Execution Class Classification (EXC):
    • EXC 1: Primarily statically loaded secondary structures (e.g., standard residential balustrades, domestic canopies).
    • EXC 2: Standard multi-storey frames, load-bearing frameworks, escape stairs, and industrial halls (the standard baseline for Swiss metal fabricators).
    • EXC 3: Dynamically loaded fatigue-critical structures, stadium cantilevers, highway, and railway bridges.
  • Declaration of Performance (DoP) and Swiss Conformity Marking: Every delivery must include a project-specific DoP detailing material grades, welding inspection levels, and corrosion protection classes (C1 to C5 under ISO 12944).
  • Mill Certificate Traceability: Mandatory archiving of 3.1 inspection certificates under EN 10204 for structural hollow sections, beams, and plates with mill heat numbers assigned to active shop orders.
Mandatory FPC Certification: A metal fabricator can only legally manufacture and erect load-bearing structural assemblies if certified under an audited Factory Production Control (FPC) system. Missing FPC documentation leads to immediate refusal of building handover by site engineers.

2. Factory Production Control (FPC) and Welding Quality Assurance (ISO 3834 / ISO 9606-1)

The Factory Production Control framework governs the entire fabrication process:

  1. Welding Coordination under ISO 3834: Documenting the designated Responsible Welding Coordinator (RWC) holding valid IWS or IWE qualifications.
  2. Welder Qualification Tracking (ISO 9606-1): The database tracks 6-month prolongation and 2-year re-qualification dates for certified welders, automatically blocking expired operators from structural weld joints.
  3. Welding Procedure Specifications (WPS / WPQR): Linking shop fabrication drawings directly to qualified WPS procedures (joint design, welding position, filler metal grade, and preheat temperature).

3. Façade Perimeter Detailing and Thermal Breaks under SIA 331 & SIA 271

Curtain wall mullion-transom assemblies and metal windows must satisfy rigorous building physics standards:

  • Window and Façade Standard SIA 331: Compliance with air permeability (Class 4 under EN 12207), watertightness under driving rain (Class 9A under EN 12208), and wind load resistance.
  • Thermal Break Calculations and U-Values: Computational verification of thermal isolators meeting Swiss cantonal energy standards (MuKEn / Ucw and Uw limits ≤ 1.0\ W/(m2K)).
  • Threshold Waterproofing under SIA 271: Detailing flush threshold lift-and-slide doors using integrated perimeter linear drainage channels and cold-applied liquid waterproofing interfaces.

4. BKP 221 Billing, Site Erection Auditing, and SIA 118 Handover Records

Site management and contractual billing follow Swiss NPK catalog positions under BKP 221 (Windows, External Doors, Gates, and Metal Façades):

  • High-Strength Bolting Torque Protocols: Documenting calibrated torque values on preloaded structural bolted joints (EN 14399 HR/HV assemblies) using calibrated torque wrenches.
  • Daywork and Variation Management under SIA 118: Capturing on-site structural modifications, crane standby delays, and interface adaptations with digital signatures from the site architect.
  • As-Built Handover Dossiers: Automated compilation of material inspection certificates, coating test logs (Qualicoat for powder coating, Qualanod for anodising), and structural maintenance schedules.

5. Comparative Overview: Physical Workshop Binders vs. Integrated Metalwork ERP Database

| Operational Benchmark | Paper Binders & Spreadsheets | Integrated ACCSoft Metalwork Database | | :--- | :--- | :--- | | EN 1090 FPC Compliance | Tedious manual searching across delivery slips | Automated audit trail linking mill certificates to final DoP | | Welder Qualification Status | Missed prolongation and expiry dates | Early warning notifications and automated allocation blocks | | Steel Heat Number Traceability | Lost paper mill test reports | Instant one-click retrieval of 3.1 inspection certificates | | Thermal Verifications (SIA 331) | Dispersed external physics reports | U-values embedded directly in fenestration element data | | Site Erection Quality Records | Missing bolting torque inspection sheets | Digital checklists with photos and calibrated torque logs |

6. Statutory Framework and Official Resources