The National Association of Home Builders (NAHB) and the International Code Council (ICC) recently announced the release of the ICC 700-2025 (fifth edition) National Green Building Standard (NGBS).
Developed through an independent consensus committee, the NGBS serves as a comprehensive framework for defining and verifying high-performance residential construction across the United States, including a rigorous, points-based system. Awards include Bronze, Silver, Gold or Emerald ratings, based on a project’s environmental impact. The standard continues to categorize “Enhanced Fenestration” as a key method for earning points.
With more than 750,000 homes certified under the NGBS program, product manufacturers and dealers are well advised to understand how the latest version differs from previous iterations.
“The 2025 NGBS represents nearly two decades of progress and innovation in sustainable residential construction and remodeling,” said Bill Owens, NAHB chairman and a builder and remodeler from Worthington, Ohio. “This edition expands the possibilities for high-performance, resilient and low-carbon homes that meet the evolving needs of both the housing industry and homeowners.”
One of the most notable changes includes how residential properties with multiple existing buildings can now earn a property-level certification. This new approach allows developers to recognize the performance of an entire site rather than just individual buildings. Based on how the approach is structured, for door and window dealers, this could lead to larger, site-wide contracts for standardized retrofits in multi-building communities, as builders seek property-wide ratings.
The 2025 edition also introduces a new section dedicated to resilience practices, reflecting a focus on disaster preparedness and recovery. Projects earn points by performing vulnerability assessments for hazards such as wind, floods and wildfires. With that comes an incentive for manufacturers to emphasize high-performance products, such as impact-rated windows or fire-rated doors that align with “Designing for Natural Hazards” guidelines.
The 2025 NGBS also sets more aggressive energy efficiency targets, reflecting updates in national energy codes. Compliance pathways now frequently reference the 2024 International Energy Conservation Code (IECC) and to reach the highest level of certification (Emerald), projects must often demonstrate net-zero energy performance through advanced modeling.
Recognizing “Enhanced Fenestration” as a key method for earning points, specific U-factor and solar heat gain coefficient (SHGC) requirements are tailored to climate zones. For instance, windows in Climate Zone 4 that achieve a U-factor of 0.25 earn more points than the baseline prescriptive requirements. The standard also now explicitly recognizes dynamic glazing as a means to satisfy SHGC requirements, provided it is automatically controlled to control solar gain.
While previous versions established a foundation for moisture management, the 2025 standard reinforces mandatory practices for all openings. Flashing is mandatory around all exterior doors, windows and skylights, following manufacturer instructions, or they can be specified by a registered design professional.
Air leakage limits also include a critical mandatory threshold. Windows and sliding glass doors are limited to an infiltration rate of 0.3 cfm/ft², while swinging doors must not exceed 0.5 cfm/ft². The only major exception is for Jalousie windows in tropical zones, which are allowed a rate of 1.3 cfm/ft² provided they serve as the conditioned space boundary.
Of course, the standard is about more than just performance. It also reflects a growing demand for transparency regarding the environmental impact of building materials. Builders can earn points toward the “Resource Efficiency” category by installing products that provide Type III Environmental Product Declarations (EPDs). Manufacturers who provide EPDs, either industry-wide or product-specific, help builders to reach certification thresholds more easily.
Another route for fenestration includes expanded points for Universal Design elements. All interior and exterior door handles must be levers rather than knobs to qualify. Additionally, “no-step” entrances must provide at least a 32-inch-wide clearance.
The standard also recognizes the rise of automation, granting points for window treatments and door locks that are controllable via wireless or voice-activated devices.
For door and window dealers, it’s important to note that any replacement products—including sashes and glazing—must now meet current IECC U-factor and SHGC specifications to comply with the mandatory energy path for existing buildings.
By aligning products with the new resilience, transparency and performance benchmarks in the NGBS, door and window companies can give themselves an edge by acting as partners for builders navigating the new standard and certification process.
Meanwhile, “We are committed to continually advancing codes and standards,” said ICC CEO, John Belcik. “Together, with NAHB, we are proud to introduce this updated standard for high‑performance buildings, which is an achievement born from a longstanding, collaborative relationship.”