July 2026: New Glass and Ceramics Standards Boost Building Performance

The glass and ceramics industries have taken a significant stride forward in July 2026, with the publication of two pivotal international standards: ISO 9050:2026 and ISO 10292:2026. These new documents formalize state-of-the-art approaches for assessing glazing performance in buildings, affecting lighting, energy efficiency, thermal comfort, and sustainability. Industry leaders, engineers, architects, and compliance professionals will find these updates essential as they inform design, selection, and regulatory strategies for glass products and assemblies. This article provides an in-depth exploration of both standards, their practical implementation, and what they mean for anyone invested in builidng envelope performance.

Overview / Introduction

Glass and ceramics materials are more integral than ever to modern architecture and construction, not only defining aesthetics but directly influencing building performance, occupant comfort, and sustainability metrics. As energy codes grow more stringent and clients demand resilient, adaptive facades, understanding and complying with the latest standards becomes a competitive necessity. The July 2026 updates—ISO 9050:2026 and ISO 10292:2026—set new benchmarks for evaluating the optical and thermal properties of glazing. This article will:

• Demystify the technical requirements of each standard
• Highlight major changes and innovations compared to prior editions
• Analyze the impact on project teams and manufacturers
• Recommend actionable steps for compliance and best practice

Detailed Standards Coverage

ISO 9050:2026 – Luminous and Solar Characteristics of Glazing

Glass in building — Determination of luminous and solar characteristics of glazing

This major revision of ISO 9050 addresses the demanding needs of today's building projects for precise, reliable metrics on glazing performance. Its core function is to describe methodologies for quantifying how glazing interacts with visible and solar radiation—factors critical to daylighting, energy management, and glare control.

Scope and Application

ISO 9050:2026 applies to nearly all transparent glazing materials deployed in vertical and horizontal apertures—ranging from conventional clear or tinted glass to solar-control, absorbing, or reflecting products. It also introduces comprehensive guidance for complex assemblies such as double or triple glazing units, and, critically, building-integrated photovoltaic (BIPV) glazing. It expressly excludes materials strongly transmitting in the 5 to 50 µm far-infrared range (such as select plastics) and vacuum insulating glass (VIG), for which ISO 19916-1 should be consulted.

Key Requirements & Specifications

• Spectral Analysis: Mandates calculation of spectral transmittance and reflectance (300–2500 nm)
• Luminous and Solar Parameters: Requires evaluation of total light transmittance, solar direct transmittance and reflectance, total solar energy transmittance ('g value'), and ultraviolet (UV) transmittance
• Advanced Assemblies: Provides formulae and a matrix method for single, double, and triple glazing, as well as guidance for laminated and screen-printed glass
• BIPV Integration: New in this edition—a method for determining the solar and luminous properties of BIPV glazing, supporting the integration of energy-generating facade elements
• Additional Indices: Defines shading coefficient, CIE damage factor, skin damage factor, and general color rendering index, aiding nuanced material selection and specification
• Measurement Best Practices: Outlines instrumentation, integrating sphere requirements for light-scattering materials, and standardized test reporting

What’s New in the 2026 Edition?

This standard is substantially updated from its previous (2003) edition:

• Revised formula for internal heat transfer coefficient
• Updated UV transmittance determination (total range only, not split in UVA/UVB)
• Enhanced definitions for normalized solar spectral distributions
• Comprehensive procedures for laminated, screen-printed, and BIPV glazing
• Matrix method now enables streamlined calculation of properties for complex multi-pane units
• Example calculations for color rendering index

Who Needs to Comply

• Glass manufacturers
• Façade engineers and system fabricators
• Architectural designers focusing on daylighting or energy compliance
• Sustainability consultants and energy modelers

Practical Implications

By standardizing luminous and solar property measurement, ISO 9050:2026 makes it far easier to compare different glazing products and predict their real-world performance in lighting, cooling, and heating load calculations. This transparency supports smarter choices, optimized energy use, and mitigates compliance risk during code evaluations or green building certifications.

Key highlights:

• Newly introduced methodology for BIPV glazing property assessment
• Matrix calculation method for multi-layer assemblies
• Revised heat transfer and UV transmittance procedures

Access the full standard:View ISO 9050:2026 on iTeh Standards

ISO 10292:2026 – Thermal Transmittance (U Value) of Glazing

Glass in building — Determination of thermal transmittance (U value) — Calculation method

ISO 10292:2026 formalizes the calculation protocols for the thermal transmittance—commonly known as the 'U value'—of glass and glazing units. U values are central to thermal performance assessment, affecting both regulatory compliance and occupant comfort.

Scope and Application

The standard is universally relevant to single, double, and multiple glazing units composed of glass or glass-ceramic materials that are not transparent in the far-infrared (including soda lime, borosilicate, alkaline earth silicate, alumino-silicate). Both uncoated and coated types are covered. The standard specifically excludes vacuum insulating glass and systems featuring infrared-transparent interlayers or spacers.

Key Requirements & Specifications

• Detailed Calculation Method: Specifies formulae for assessing U values based on the thickness, resistivity, and conductance of each material and gas space in a glazing unit
• Thermal Conductance Components: Integrates the effects of solid layers and interlayers, along with gas-space conductance (per detailed iterative and radiative/convective models)
• Boundary Conditions: Declares standardized requirements for calculating declared U values under consistent assumptions (typically vertical position, standardized temperatures)
• Component Independence: Focuses calculations on the central glazing area—excluding edge effects, window frames, and applied bars
• Gas Properties and Heat Flow: Offers improved models for different gas fills (argon, krypton, etc.), and adapts for various installation angles
• Reporting Protocols: Provides a clear structure for U-value test reports, ensuring transparency and replicability

What’s New in the 2026 Edition?

• Updated gas properties and inclusion of a linear approximation for gas property determination at varying temperatures
• Streamlined consistency with ISO 6946 and ISO 10077-1 regarding internal heat transfer coefficients and non-vertical glazing
• Step-by-step iteration protocols for complex multi-spacer, multi-gas units

Who Needs to Comply

• Glazing unit manufacturers and system integrators
• Building envelope engineers and specifiers
• Energy modelers, thermal consultants, and compliance officers
• Certification bodies and third-party testing labs

Practical Implications

ISO 10292:2026 gives project teams a robust, repeatable pathway to declaring U values for product labeling, energy code compliance, and green building submissions. The clarified procedures help ensure consistency regardless of product complexity or configuration.

Key highlights:

• Expanded guidance for calculating U values of multi-space glazing
• Precise modeling of radiative and convective heat exchanges
• Standardized boundary conditions aligned with global codes

Access the full standard:View ISO 10292:2026 on iTeh Standards

Industry Impact & Compliance

The adoption of ISO 9050:2026 and ISO 10292:2026 will have far-reaching effects across the construction, architecture, and building products sectors:

• Design Optimization: More accurate and comparable data improves specification, allowing façade designers to balance daylight, solar gain, and insulation for optimal comfort and efficiency.
• Building Codes and Sustainability: Meeting or exceeding current energy performance standards (such as those required by LEED, BREEAM, or national codes) is streamlined—both standards are globally recognized benchmarks.
• Risk Mitigation: Using harmonized, transparent methods for glazing properties reduces liability when demonstrating compliance in permitting and certification.
• Product Development: Manufacturers can use these standards to substantiate performance claims and target emerging market needs (e.g., integration of photovoltaics, advanced coatings).

Compliance Considerations and Timelines:

• Transition to the new standards should be immediate for new designs, while existing certified products may require retesting or recalculation as required by local authorities.
• Both standards specify thorough test reporting and traceability—critical for audits or certification.
• Early engagement with test labs or certification bodies familiar with the 2026 criteria will streamline compliance.

Benefits of Adoption:

• Enhanced market competitiveness
• Streamlined global trade through harmonized metrics
• Stronger reputation for quality, performance, and sustainability

Risks of Non-Compliance:

• Increased risk of failed inspections or code disputes
• Potential rework and cost overruns
• Lost eligibility for green building incentives or programs

Technical Insights

Common Requirements Across Both Standards

• Both require precise characterization of material properties, especially spectral and thermal behavior.
• Advanced calculation methods (including matrix and iterative models) are embedded, driving accuracy for complex, multilayered, or coated units.
• Both demand thorough documentation: detailed test reports, material identification, and reference to specific standard versions are mandatory.

Implementation Best Practices

1. Material Characterization:

   • Engage certified labs for optical and thermal measurements.
   • Employ proper calibration, especially for spectrophotometers and integrating spheres (per ISO 9050 guidance).

2. Modeling and Calculation:

   • Use software tools that incorporate matrix methods or iterative processes for spectral and U value calculations.
   • Keep detailed records of layer types, thicknesses, coatings, and gas fills.

3. Reporting:

   • Structure reports as prescribed in both standards, including pane identification, configuration, and calculated/transmitted values.

4. Testing and Certification:

   • Align with third-party certification schemes that reference ISO 9050 and ISO 10292 for additional assurance, especially in regulated or export markets.

Testing and Certification Considerations

• For ISO 9050, integrating sphere size and proper averaging is crucial for scattering or patterned materials.
• For ISO 10292, edge effects are excluded—ensure thermal modeling at the central area.
• Both standards reference ISO 20589 for emissivity determination; ensure up-to-date calibration and lab capabilities.

Conclusion / Next Steps

With the July 2026 rollout of ISO 9050 and ISO 10292's latest editions, professionals in the glass and ceramics sector have clear, robust frameworks for assessing glazing performance. The expanded methods for BIPV, multi-layer units, and advanced thermal modeling make it easier than ever to specify, model, and certify high-performance envelopes. Organizations should:

• Review current products and projects for alignment with the new standards
• Update internal specifications and compliance checklists
• Train teams in the new calculation and reporting protocols
• Collaborate with accredited laboratories for testing and validation

In the rapidly evolving field of building materials, staying current with the latest standards is not only a compliance necessity but a strategic imperative for quality, sustainability, and market leadership.

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