Navigating the 2025 NGBS

The 2025 edition of the National Green Building Standard (ICC 700) is arriving just as buyers, lenders and government agencies are paying closer attention to home performance and affordability. For small and mid-size builders, that can feel like one more thing to keep up with.

The good news is that the 2025 NGBS is not a reinvention. It is an evolution that raises expectations in a few key areas while keeping the flexible, points-based structure that has made it workable for real-world projects. If you already build above code, participate in energy or water programs or offer “high-performance” options, you are closer to it than you may think.

The most visible change in the 2025 NGBS is a modest expansion of mandatory practices. Builders will see clearer expectations for construction waste planning and diversion, ventilation system performance, radon testing and duct leakage testing. These are not exotic ideas. Many builders are already doing versions of them to meet their building code, qualify for rebates or cut down on callbacks.

What has not changed is the way the NGBS is organized. The standard still relies on a broad menu of optional practices that allow you to choose the most cost-effective path for your climate, product type and buyer profile. You can pursue “just above code” performance or push toward higher levels in the same framework. That flexibility is key. The 2025 NGBS tightens the floor in a few places but does not force every project into the same prescriptive package or performance target.

Energy is where many builders expect big changes and the 2025 NGBS does something important here it becomes more nuanced, not more rigid. Electrification and lower-carbon designs receive stronger recognition, but the standard does not require that every home be all-electric. Instead, it broadens how projects can demonstrate performance improvement. Depending on your strategy, you can show gains using traditional cost-based metrics, site energy, source energy and carbon emissions.The point is that the NGBS gives you options. It recognizes different ways to reach better performance, instead of locking you into a single energy story that may not match your market conditions or buyers’ budgets.

“Resilience” has been a buzzword for years. The 2025 NGBS pushes it toward something more concrete. The updated standard calls for looking at real hazard exposure, considering hazard-specific design strategies and paying more attention to passive survivability and resilient energy systems. It also introduces new wildfire-related site practices where those risks apply.

For builders, this does not mean redesigning every plan around worst-case scenarios. It means asking a few focused questions earlier in the process. Framed this way, resilience becomes a practical design and sales conversation. It is something you can use to differentiate your homes and respond to concerns from insurers and local officials.

Two other areas see meaningful modernization, water efficiency and indoor air quality. On the water side, the 2025 NGBS clarifies minimum expectations for prescriptive projects, updates the Water Rating Index and provides clearer rules for outdoor water use and reuse systems. This tracks with rising water rates and growing attention to drought and supply risk, not just in the West but in many markets. On the IAQ side, ventilation and exhaust provisions are tuned to how homes are actually being built and operated today and radon measures are strengthened. Optional practices for IAQ monitoring and automated remediation reflect a growing segment of buyers who care about more than just “meets code.”

For builders, the main lesson is timing. Ventilation design, duct layout and outdoor water strategies are least expensive when they are considered in schematic design and mechanical coordination. They are most expensive when they show up as late surprises. 

Certification is what turns ‘we build to a higher standard’ from a promise into a verified fact. Certification can support your brand, your risk management, access to incentives and boost appraisal value. For many builders, it is a straightforward way to get greater value for practices they are already putting into the homes.

For many builders, the 2025 NGBS will not require starting from scratch. It will require tightening some practices you are already doing, being more deliberate about energy and water strategies and deciding where NGBS Green certification supports your brand and bottom line.

Approached that way, the new edition is less a hurdle to clear and more a tool to help you navigate where the market is headed.

Michelle Foster is the Vice President of Home Innovation Research Labs, NGBS Green certification program. She may be reached at mfoster@homeinnovation.com.  

This is featured in the Green Home Builder February issue, read the print version here.