Introduction
The global construction industry is navigating its most significant regulatory transformation in a generation. Governments across North America, Europe, Australia, and the Middle East are simultaneously tightening energy efficiency codes, expanding embodied carbon requirements, and mandating green building certifications - creating a complex but critical landscape for anyone specifying sustainable building materials in 2026.
For fenestration - windows, doors, and glazed facades - the stakes are particularly high. Windows and external doors account for 25–40% of a building's heating and cooling energy losses in typical residential and commercial construction. This makes them a primary target for regulatory intervention and, simultaneously, a major opportunity for energy performance optimization.
At SGL Doors & Windows, we work with architects, developers, and contractors across 30+ countries navigating these evolving requirements. This guide synthesizes the most important 2026 regulatory developments affecting window and door specification globally, with practical guidance on compliance and specification optimization.
The Global Regulatory Picture: Key Themes for 2026
Theme 1: Net Zero Building Targets Accelerating
The convergence of national net zero commitments (Paris Agreement pathways, national Climate Acts) with building sector regulations is generating rapid code tightening:
| Country / Region | Net Zero Building Target | Key Regulatory Mechanism |
|---|---|---|
| UK | All new homes net zero ready by 2025 (Future Homes Standard) | Part L 2022 (intermediate), Future Homes Standard (2025 full) |
| EU | EPBD recast - all new buildings zero-emission by 2028 | EU Energy Performance of Buildings Directive (EPBD) |
| Australia | NCC 2025 energy efficiency upgrade | 7-star NatHERS rating now required for new Class 1 homes |
| Canada | NECB 2020 (adoption ongoing by province) | National Energy Code for Buildings |
| USA | IECC 2021/2024 (state-by-state adoption) | International Energy Conservation Code |
| UAE | Green Building Regulations (Dubai Municipality) | Pearl Rating System (Abu Dhabi), Al Sa'fat (Dubai) |
Critical Insight: Regulatory timelines are compressing. Projects that specified to 2022 standards may find their designs non-compliant by the time they reach permit submission or practical completion. Early-stage sustainability assessment is now essential project management practice.
Theme 2: Embodied Carbon Is Entering Regulation
For the past decade, sustainable building regulations have focused almost exclusively on operational carbon - the energy used to run buildings (heating, cooling, lighting). In 2026, embodied carbon - the carbon footprint of manufacturing the building materials themselves - is entering mandatory regulation for the first time in several key markets:
Embodied Carbon Regulatory Milestones:
- UK: RIBA 2030 Climate Challenge targets include whole-life carbon. Several local authorities (London, Manchester) now require Whole Life Carbon Assessments (WLCA) for planning approval.
- Netherlands: MPG (Milieuprestatie Gebouwen) embodied carbon limit mandatory for new buildings since 2021; threshold tightening in 2025.
- France: RE2020 (in force from 2022) includes embodied carbon limits in the Ic_construction metric - the first major national code to do so.
- USA: Buy Clean policies (federal procurement + California, Washington state law) require Environmental Product Declarations (EPDs) for building materials.
- Australia: Green Star buildings increasingly require embodied carbon assessments; voluntary 2025 target framing for future mandatory adoption.
For fenestration products, this means:
- Environmental Product Declarations (EPDs) are increasingly requested by specifiers
- Aluminum windows with recycled content or renewable energy manufacturing gain competitive specification advantage
- Supply chain transparency (mill certificates, recycled content declarations) is becoming a commercial requirement, not just a sustainability aspiration
SGL Action: We are actively developing Environmental Product Declarations (EPDs) for our aluminum and steel product ranges, and our manufacturing facility uses a growing proportion of recycled aluminum feedstock - with 60%+ recycled content in standard aluminum alloy profiles.
Theme 3: Mandatory Green Certification Expansion
Green building certification systems - previously voluntary differentiators - are increasingly being mandated by government policy, lending conditions, and major commercial tenants:
| Certification | Region | Mandatory? | Key Requirement |
|---|---|---|---|
| LEED (Leadership in Energy & Environmental Design) | Global (US-led) | Voluntary (mandatory for US federal buildings) | Energy performance, IEQ, materials |
| BREEAM | UK / International | Voluntary (mandatory some UK local authorities) | Energy, materials, water, transport |
| Green Star | Australia / NZ | Voluntary (mandatory for some government projects) | Energy, IEQ, materials, water |
| NABERS | Australia | Mandatory for commercial office >1000m² (energy) | Measured energy performance |
| Pearl Rating System | Abu Dhabi | Mandatory for government projects | Holistic sustainability |
| Al Sa'fat | Dubai | Mandatory for all buildings | Energy, water, site |
| RE2020 | France | Mandatory for new homes | Energy + embodied carbon |
| DGNB | Germany / Nordic | Voluntary (growing public procurement) | Life-cycle sustainability |
The commercial implication: Major institutional tenants (government departments, large corporations with ESG commitments) are increasingly refusing to lease buildings without BREEAM Excellent, Green Star 5-Star, or LEED Gold minimum. For developers, this makes green certification not just a regulatory compliance issue but a commercial necessity for tenantability.
Fenestration-Specific Regulations: Deep Dive
United Kingdom: Future Homes Standard & Part L 2022
The UK's journey to net zero buildings is proceeding in two stages for fenestration:
Part L 2022 (Currently in Force):
- New homes must achieve a 31% improvement in energy performance versus the 2013 baseline
- Window U-values tightened: typical compliant whole-window U-value now ≤ 1.4 W/m²K for dwellings
- Summer overheating check (TM59 for apartments) is now a compliance requirement, affecting SHGC/g-value specification
Future Homes Standard (FHS) - 2025/2026 Full Implementation:
- Targets 75–80% CO₂ reduction versus 2013 baseline
- Implied U-values for windows: ≤ 1.2 W/m²K for high-performing envelope designs
- Transition: Certain provisions taking effect in 2026 as FHS secondary legislation is finalized
- Impact: Projects designed to Part L 2022 minimums will NOT comply with FHS. Architects should specify to FHS performance now to avoid redesign.
SGL Products for UK Compliance:
- Thermal-break aluminum windows: U-values from 1.0–1.4 W/m²K (product and glazing dependent)
- Triple-glazed aluminum systems: U-values ≤ 1.0 W/m²K achievable
- UPVC windows: Inherently good U-values (1.2–1.4 W/m²K with double glazing)
Australia: NCC 2025 - 7-Star Energy Rating
Australia's National Construction Code (NCC) 2025 represents the most significant update to residential energy requirements in 15 years:
Key Changes Affecting Fenestration:
- New Class 1 (residential) buildings: Minimum 7-star NatHERS rating (up from 6 stars in most states)
- Window energy ratings: Window Energy Rating Scheme (WERS) ratings now critical for NatHERS compliance modeling
- SHGC as important as U-value: Solar Heat Gain Coefficient optimization is essential for compliance in hot climate zones (Queensland, WA, NT)
- Ceiling fans + natural ventilation: Encouraging operable window designs for natural ventilation credit
What This Means for Window Specification:
In hot climate zones, lower SHGC (0.2–0.4) is often more impactful than low U-value. In cold climate zones (Victoria, Tasmania, ACT), low U-value (≤ 2.0 W/m²K) is the priority. Many projects will need climate-zone-specific glazing specifications rather than a single national product selection.
SGL's NCC 2025 Capability:
- WERS-rated products available for Australian market projects
- AS2047 certified across the range
- Solar control glazing options (tinted, Low-E coatings, triple glazing) to achieve required SHGC
United States: IECC 2021 / 2024 Update Cycle
The US energy code landscape is complex due to state-by-state adoption, but a clear trend toward the IECC 2021 or 2024 baseline is evident:
Key IECC Requirements for Fenestration:
| Climate Zone | Max U-Factor (Windows) | Max SHGC |
|---|---|---|
| Zone 1–2 (Hot: FL, TX south, HI) | 0.40 (2.3 W/m²K) | 0.25 |
| Zone 3 (Mixed: CA coast, GA) | 0.30 (1.7 W/m²K) | 0.25 |
| Zone 4 (Mixed-humid: VA, MO) | 0.27 (1.5 W/m²K) | 0.40 |
| Zone 5 (Cool: OH, PA, NY) | 0.27 (1.5 W/m²K) | NR |
| Zone 6 (Cold: MN, WI, MT) | 0.27 (1.5 W/m²K) | NR |
| Zone 7–8 (Very cold: AK, ND) | 0.22 (1.25 W/m²K) | NR |
NR = No requirement; SHGC may be beneficial but not mandatory
Notable trend: Several states (California, New York, Washington, Colorado) are adopting beyond-IECC minimums, pushing toward passive house-aligned standards for new commercial and multifamily buildings. Projects in these states should plan for U-factors of ≤ 1.2 W/m²K for windows.
UAE & GCC: Green Building Mandates
The UAE has established two major green building frameworks with mandatory application:
Dubai: Al Sa'fat Green Building Rating System
- Mandatory for all buildings since 2016, updated 2024
- Energy credits require glazing U-value and SHGC performance documentation
- Window-to-wall ratio (WWR) limits and shading requirements
- Solar heat gain control critical in Dubai's extreme solar climate
Abu Dhabi: Pearl Rating System
- Mandatory for government buildings, strongly encouraged for private
- Similar fenestration energy performance documentation requirements
Saudi Arabia Vision 2030 - Green Building Push:
- ARAMCO, NEOM, and major government projects adopting LEED / BREEAM
- Saudi Green Building Forum driving voluntary adoption ahead of expected mandatory frameworks
Key specification requirement for the region:
- SHGC ≤ 0.25 typically required for the UAE climate
- External shading (overhangs, fins) combined with high-performance glazing
- Civil Defense approval for all fire-rated products (mandatory)
Sustainable Fenestration Selection Framework
Step 1: Identify Applicable Codes & Certifications
Before specifying any product, establish:
- Jurisdiction: Which building code applies (IECC zone, NCC climate zone, Part L region)?
- Certification requirement: Is green certification (LEED, BREEAM, Green Star) required or commercially necessary?
- Building type: Residential, commercial, or mixed-use (different requirements apply)?
- Project timeline: Will FHS, IECC 2024, or NCC 2025 apply at permit submission?
Step 2: Establish U-Value and SHGC Targets
| Climate | Priority | Target U-value | Target SHGC |
|---|---|---|---|
| Cold (Canada, Nordic, UK North) | U-value | ≤ 1.2 W/m²K | NR (high acceptable) |
| Temperate (UK South, AU Victoria) | Balanced | ≤ 1.4 W/m²K | 0.35–0.50 |
| Hot-arid (UAE, AU QLD, US Zone 1-2) | SHGC | ≤ 2.0 W/m²K | ≤ 0.25 |
| Mixed (US Zone 3-4, AU NSW) | Both | ≤ 1.6 W/m²K | 0.25–0.40 |
Step 3: Frame Material Selection
| Frame Material | Inherent Thermal Performance | Notes |
|---|---|---|
| UPVC | Good (no thermal break needed) | Low embodied carbon vs aluminum; excellent U-values naturally |
| Aluminum (standard) | Poor (high conductivity) | REQUIRES thermal break for energy code compliance |
| Aluminum (thermal break) | Good | Polyamide break; U-values achievable ≤ 1.2 W/m²K |
| Steel (standard) | Poor | High conductivity; fine for heritage but thermally limited |
| Steel (thermal break) | Good | Polyamide or PU foam break; rare but available for premium projects |
| Composite (timber-aluminum) | Excellent | Warm interior, durable exterior; highest cost |
Step 4: Glazing Specification
The glazing unit (not just the frame) typically dominates thermal performance in well-designed systems:
| Glazing Type | Typical U-value | Typical SHGC | Application |
|---|---|---|---|
| Single glazing | 5.5–6.0 W/m²K | 0.85 | Heritage/listed buildings only |
| Double glazing (air) | 2.6–2.9 W/m²K | 0.65–0.75 | Budget projects, warm climates |
| Double glazing (argon) | 1.8–2.4 W/m²K | 0.65–0.75 | Standard residential |
| Double glazing (Low-E + argon) | 1.0–1.6 W/m²K | 0.25–0.50 | Most regulated markets |
| Triple glazing (Low-E + argon) | 0.6–0.9 W/m²K | 0.25–0.45 | Cold climates, near-passive |
| Triple glazing (krypton) | 0.5–0.7 W/m²K | 0.20–0.35 | Passive house, highest performance |
Sustainability Certifications for Fenestration Products
When specifying windows and doors for certified green buildings, the product's own certification status matters alongside the building-level compliance:
Energy Rating Certifications
| Rating Scheme | Region | What It Provides |
|---|---|---|
| WERS (Window Energy Rating Scheme) | Australia | Star rating for heating/cooling energy performance |
| NFRC Label | USA | Certified U-factor and SHGC values for compliance |
| British Fenestration Rating Council (BFRC) | UK | Energy rating A++–G for windows (Window Energy Ratings) |
| Passive House Institute (PHI) | Germany / Global | Certified ultra-low energy component rating |
| CE Marking (EN 14351-1) | EU / UK | Performance Declaration including thermal transmittance |
Environmental Product Declarations (EPDs)
An EPD is a standardized document (ISO 14025) that transparently communicates a product's lifecycle environmental impacts, including:
- Global Warming Potential (GWP) - the embodied carbon figure
- Primary Energy Demand (PED)
- Acidification, Eutrophication, Ozone Depletion
EPDs are becoming the currency of sustainable specification. In markets with embodied carbon regulation (France RE2020, Netherlands MPG, UK voluntary/emerging mandatory), EPD data is required for compliance calculations.
For aluminum windows specifically:
- Recycled content dramatically reduces GWP - 1 kg of primary aluminum ≈ 11 kg CO₂; 1 kg of recycled aluminum ≈ 0.6 kg CO₂ (95% reduction)
- Specifying aluminum products with declared post-consumer recycled content is an immediate sustainability improvement
- SGL is developing ISO 14044-compliant lifecycle assessments and EPDs across product lines
Common Specification Pitfalls in Sustainable Projects
❌ Pitfall #1: Specifying to Yesterday's Code
- Problem: Designing to 2019/2022 energy code minimums for projects with 2026+ completion dates.
- Consequence: Re-specification required mid-project; delayed approvals; potential value engineering that compromises sustainability outcomes.
- Fix: Check current applicable code at project commencement, not at product specification stage. Use FHS/IECC 2024/NCC 2025 as the design baseline now, even if not yet fully mandatory in your jurisdiction.
❌ Pitfall #2: Confusing Manufacturer Claims with Certified Performance
- Problem: Accepting U-value claims from product datasheets without verifying they are third-party certified values.
- Consequence: As-built performance differs significantly from specified performance; compliance failures at certification stage.
- Fix: Always request NFRC, WERS, BFRC, or CE performance labels and test reports. Verify that the certified U-value reflects the whole-window (frame + glazing) system, not just the center-pane glass value.
❌ Pitfall #3: Ignoring Solar Heat Gain in Mixed Climates
- Problem: Over-specifying low SHGC glazing in temperate climates where solar gain contributes meaningfully to winter heating loads.
- Consequence: Increased heating energy consumption that offsets the summer cooling savings; net energy penalty versus a balanced specification.
- Fix: Use a building energy model (e.g., IESVE, DesignBuilder, EnergyPlus) to optimize orientation-specific glazing specification. South-facing windows (northern hemisphere) should often have higher SHGC than east/west/north orientations.
❌ Pitfall #4: Neglecting Embodied Carbon
- Problem: Specifying the lowest-thermal-resistance product to hit operational energy targets without considering manufacturing carbon footprint.
- Consequence: Triple-glazed, krypton-filled windows may have significantly higher embodied carbon than well-designed double-glazed alternatives - in some buildings, the operational savings never pay back the embodied carbon premium.
- Fix: Conduct a Whole Life Carbon Assessment (WLCA) considering both operational and embodied carbon. For buildings with short design lifespans (<25 years) or excellent grid decarbonization, embodied carbon often dominates the picture.
❌ Pitfall #5: Ignoring Air Tightness as a System Issue
- Problem: Specifying high-performance windows while neglecting the perimeter air seal between window frame and structural opening.
- Consequence: Excellent product performance negated by infiltration at the installation interface; tested product performance not achieved in-situ.
- Fix: Specify system air tightness including perimeter sealing (compriband tape, expanding foam, liquid membrane) as part of the window specification. For Passive House certified projects, blower door testing will expose any installation deficiencies.
SGL's Sustainable Product Range
SGL Doors & Windows has invested in sustainable product development to meet the evolving demands of green building specification:
Our Popular Products
Aluminum Thermal Break Windows & Doors
Our thermal-break aluminum window range achieves:
- Whole-window U-values from 1.0 to 1.6 W/m²K (glazing package dependent)
- SHGC flexibility from 0.22 to 0.68 depending on Low-E glass selection
- Compatible with double and triple-glazed unit configurations
- WERS-rated for Australian compliance; NFRC data available for US projects
- CE marked with EN 14351-1 thermal transmittance declared
UPVC / PVCu Window & Door Systems
Our UPVC window and door systems offer:
- Inherently excellent thermal performance without added thermal breaks
- Typical whole-window U-values 1.2–1.6 W/m²K with standard double glazing
- Fully recyclable at end-of-life (cradle-to-cradle)
- Available in recycled-content profiles (post-industrial recycled PVC available)
- Lower embodied carbon than equivalent aluminum alternatives in most lifecycle scenarios
Low Embodied Carbon Aluminum
We supply aluminum profiles with up to 60% post-consumer recycled content, dramatically reducing the GWP versus primary aluminum production:
- GWP reduction of up to 40% versus standard primary aluminum products
- Suitable for projects requiring EPD or embodied carbon declaration
- No compromise on mechanical or aesthetic performance
Glazing Options
We work with leading glazing manufacturers to offer:
- Low-E double glazing - optimized for each market's climate balance
- Solar control glazing - for hot-climate SHGC compliance (SHGC ≤ 0.25 achievable)
- Triple glazing - for cold-climate and near-passive-house performance
- Acoustic glazing - for urban noise reduction alongside thermal performance
Conclusion: Sustainable Specification Is a Competitive Advantage
The trajectory is clear: sustainable building regulations will only get stricter, and the window to adapt is now. For architects and developers who get ahead of the compliance curve, sustainable specification creates competitive advantages:
- Future-proofed designs that don't require expensive re-specification at permitting
- Green certification that commands premium rental rates and sale prices (1.5–8% premium documented in multiple market studies)
- Embodied carbon leadership that satisfies ESG commitments of major institutional tenants and investors
- Energy cost protection for building occupants - increasingly valued in an era of energy price volatility
At SGL Doors & Windows, we understand that sustainable specification begins at the product selection stage. Our technical team is equipped to provide:
- U-value and SHGC performance data for compliance calculations
- WERS-rated and NFRC-certified product data for compliance documentation
- Climate-zone-specific recommendations for glazing and frame specification
- EPD development in progress for key product ranges
Ready to specify for sustainable compliance? Contact our technical team for project-specific product recommendations and energy performance documentation.
FAQ
Q: Q1: What U-value do windows need to meet UK Future Homes Standard?
A: A: The UK Future Homes Standard (full implementation in progress through 2025–2026) targets a whole-dwelling energy performance 75–80% better than 2013 baselines. In practice, this typically requires whole-window U-values of ≤ 1.2 W/m²K for most dwelling configurations, though the exact requirement depends on the building's overall energy balance and the specification approach used. SGL's thermal-break aluminum and UPVC systems can achieve these targets with appropriate glazing selection.
Q: Q2: What does the NCC 2025 7-star rating mean for window specifications in Australia?
A: A: Under the NCC 2025, all new Class 1 (detached house, townhouse) buildings must achieve 7-star NatHERS rating (up from 6 stars). For windows, this typically means selecting products with WERS ratings optimized for your climate zone - emphasizing SHGC control in hot zones (QLD, WA, NT) and U-value performance in cold zones (VIC, TAS, ACT, alpine areas). SGL provides WERS-rated products and can support NatHERS compliance modeling with product performance data.
Q: Q3: What is an Environmental Product Declaration (EPD) and why does it matter for 2026 projects?
A: A: An EPD (Environmental Product Declaration) is an ISO 14025-compliant document that discloses a building product's lifecycle environmental impacts, including its embodied carbon (Global Warming Potential). In 2026, EPDs are required for compliance calculations in France (RE2020), the Netherlands (MPG), and several US jurisdictions with Buy Clean legislation. They are also increasingly requested by LEED, BREEAM, and Green Star certifications for materials credits. For aluminum window products, EPDs with declared recycled content are particularly valuable.
Q: Q4: How does SHGC affect energy performance - should I always specify low SHGC?
A: A: No - this is one of the most common fenestration specification mistakes. SHGC (Solar Heat Gain Coefficient) measures how much solar energy passes through the glass. In hot climates (UAE, Queensland, US South), low SHGC (≤ 0.25) reduces cooling loads. But in temperate or cold climates, solar gain through south-facing windows (northern hemisphere) actually reduces heating loads. Blindly specifying low SHGC in a London or Toronto building can increase annual energy consumption. Always model orientation-specific SHGC optimization.
Q: Q5: Can UPVC windows be considered sustainable?
A: A: Yes - UPVC windows have several genuine sustainability advantages: (1) lower embodied carbon than aluminum in most lifecycle scenarios, (2) no thermal break required (inherently low conductivity), (3) fully recyclable at end-of-life, (4) low maintenance reduces lifetime resource consumption. The common criticism of PVC (plastic material) overlooks the full lifecycle picture. UPVC's long service life (30–40 years) and recyclability make it an environmentally competitive choice, particularly where aluminum primary production energy is the key impact driver.
Q: Q6: Does SGL offer products that comply with LEED and BREEAM certification requirements?
A: A: Yes. SGL products can contribute to both LEED and BREEAM credits across several categories: Energy & Atmosphere (thermal performance data for energy modeling), Materials & Resources (recycled content declarations, EPDs in development), Indoor Environmental Quality (acoustic performance, daylighting glazing options), and Innovation credits (sustainable procurement documentation). Our technical team can provide product-specific documentation packages tailored to your certification submission requirements.
About SGL Doors & Windows
SGL Doors & Windows is a premier manufacturer of aluminum windows and doors, UPVC/PVCu systems, steel windows, composite doors, and glass door solutions. With ISO 9001 certification, CE marking, AS2047 certification, and WERS-rated products for the Australian market, SGL delivers high-performance, sustainable-specification-ready products to developers, architects, and contractors across 30+ countries.
Certifications: ISO 9001 | CE (EN 14351-1) | AS2047 | WERS Rated | UAE Civil Defense Approved
Sustainability: Recycled-content aluminum profiles | EPD development in progress | UPVC recyclable product range
Markets Served: USA, UK, Australia, Canada, UAE, France, Germany, Singapore, Philippines, South Africa, and more
Website: https://www.sgl-doors-windows.com
Contact for Sustainable Specification: Request Technical Documentation
Tags: sustainable windows, sustainable building materials, building regulations 2026, future homes standard, NCC 2025, IECC 2024, LEED windows, BREEAM materials, green building windows, U-value compliance, SHGC specification, embodied carbon windows, EPD fenestration, SGL sustainable products, thermal break aluminum, low carbon building
