ISO 28278-1:2011

Overview

ISO 28278-1:2011 - Glass in building - Glass products for structural sealant glazing - Part 1: Supported and unsupported monolithic and multiple glazing defines requirements for the suitability of glass products used in structural sealant glazing (SSG). It supplements the relevant glass product standards by specifying how soda‑lime silicate glass (monolithic, laminated or insulating glass units) is verified for bonded, load‑bearing glazing applications. Plastic glazing is excluded. The standard assumes installation under controlled environmental conditions (see ISO 28278‑2).

Key topics and technical requirements

• Scope and materials: Applies only to soda‑lime silicate glass for supported and unsupported glazing used with structural sealant glazing techniques.
• Sealant types: Recognizes organo‑siloxane (“silicone”) sealants as the common structural, weatherproofing and outer‑seal systems; allows other sealants only if demonstrated suitable per ISO 28278‑1 and the sealant manufacturer’s recommendations.
• Design considerations: Includes provisions for calculating glass thickness and the required height of outer seals for IGUs in supported and unsupported installations.
• Dimensional and geometric requirements: Covers dimensional tolerances, glass shapes, corners, notches and holes that affect suitability for SSG.
• Durability and ageing: Procedures for verifying performance under UV exposure and for assessing adhesion between sealant and glass.
• Testing and verification: Annexes specify test methods and evaluation criteria (e.g., shear testing at 23 °C), factory production control (FPC) requirements for sealants, initial type testing and interpretation of test results.
• Seismic and safety notes: Notes that sealant design alone may be insufficient in seismic zones and that complementary arrangements (retaining devices, mechanical support) may be required.
• Supporting documentation: Normative references include ISO 20492 (IGU), ISO 12543 (laminated glass), ISO 11600 (sealant classification), and ASTM C1184/C1265.

Practical applications and who uses this standard

ISO 28278‑1:2011 is used to ensure safe, durable bonded glazing in:

• Façade and curtain‑wall design (architects, façade engineers)
• Glass and IGU manufacturers (product specification and QC)
• Sealant manufacturers (product performance and recommendations)
• Glazing contractors and installers (assembly and acceptance criteria)
• Testing laboratories and certification bodies (type testing, FPC)
• Building authorities and specifiers concerned with structural sealant glazing performance

Related standards

• ISO 28278‑2 (Assembly rules for SSG)
• ISO 20492 (Glass in buildings - Insulating glass)
• ISO 12543 (Laminated glass)
• ISO 11600, ASTM C1184, ASTM C1265 (sealant and test methods)

ISO 28278‑1:2011 is essential for projects specifying bonded, structural glazing systems where verification of glass‑to‑sealant compatibility, dimensional control, and durability (UV, load, seismic considerations) is required. Keywords: ISO 28278‑1:2011, structural sealant glazing, SSG, soda‑lime silicate glass, IGU, silicone sealant, bonded glazing, façade engineering.