ISO 12543-5:2021

Overview

ISO 12543-5:2021 - Glass in building - Laminated glass and laminated safety glass - Part 5: Dimensions and edge finishing specifies how to measure and report the physical dimensions, permitted deviations and allowed edge finishes for laminated glass and laminated safety glass used in buildings. It applies to panes ≥ 0.05 m² and is part of the ISO 12543 series that defines laminated glazing products and their properties.

Key topics and technical requirements

• Thickness and tolerances

  • Nominal thickness = sum of nominal thicknesses of constituent glass panes, interlayers and plastic glazing sheets.
  • Limit deviations depend on product type (folio laminated, cast‑in‑place, fire‑resistant) and interlayer thickness. Example rules: folio interlayers add ±0.1 mm (≤2 mm) or ±0.2 mm (>2 mm); cast‑in‑place interlayers follow tabulated tolerances (e.g., ±0.4 mm for <1 mm, ±0.5 mm for 1–2 mm).
  • For combinations, total tolerance = sum of glass pane deviations plus the square root of the sum of squared interlayer deviations (rounded to 0.1 mm).
  • Measurement: mean of measurements taken at the centres of the four sides, measured to 0.01 mm and rounded to 0.1 mm.

• Width, length, squareness and offset

  • Dimension ordering: width B, then length H for rectangular panes.
  • Finished and stock sizes have defined upper/lower limit deviations (tables in the standard). Additional ±3 mm may apply if a component is toughened or heat‑strengthened.
  • Squareness is assessed by diagonal difference; limit values are tabulated (vary by nominal thickness and maximum dimension).
  • Offset (misalignment of constituent panes) is specified and limited (e.g., maximum offset d = 2.0 mm for B or H ≤ 2 000 mm; 3.0 mm for ≤ 3 000 mm; 4.0 mm for > 3 000 mm).

• Edge finishes

  • The standard defines acceptable edge types: cut edge, arrissed, ground, smooth ground, polished, bevel, sawn, water‑jet cut, etc., and gives general rules (e.g., thermally treated glass should not be cut or sawn after lamination unless validated by the manufacturer).

• Flatness

  • Flatness requirements and measurement methods are included (see full standard for detailed procedures and limits).

Applications and users

• Useful for: glazing manufacturers, fabricators, façade engineers, architects, specifiers, building inspectors, procurement teams and test laboratories.
• Practical uses: setting production tolerances, quality control, supplier specifications, conformity checks on delivered laminated glazing, and contract or tender documentation.

Related standards

• ISO 12543-1 (definitions and component descriptions) is a normative reference.
• The standard references basic product standards (ISO/CEN) for constituent glass and interlayer tolerances - users should consult those standards when applying ISO 12543-5.

Keywords: ISO 12543-5:2021, laminated glass, laminated safety glass, edge finishing, dimensions, limit deviations, offset, thickness, glass in building.