The point structure behind ANSI/ICC/ASHRAE 700-2023 (NGBS 2023) trips up builders who treat the four certification levels as simple multiples of one another. They are not. Bronze requires fewer mandatory practices and fewer points. Emerald requires net-zero verifiable performance plus a third-party energy model. Silver and Gold sit in the middle but pull from different point categories.
Most production builders chase Silver because it is the default spec from lenders and state housing finance agencies. Specifiers, however, frequently misread the NGBS point categories, assuming Energy Efficiency alone drives tier placement. In practice, a builder can clear Silver on points but fail Bronze on a single mandatory practice, for example, missing the ASHRAE 62.2-2022 §4.1 whole-building ventilation calculation or skipping the air-barrier inspection required by 2024 IECC R402.4.1.1.
Two other recurring failures show up in HECS plan reviews. First, designers cite "5 ACH50 in CZ 4", that is the 2018 IECC mapping. Under 2024 IECC Table R402.4.1.1, the limit is 3.0 ACH50 across Climate Zones 3 through 8. Kentucky and Indiana both fall in CZ 4A and CZ 5A, so the binding limit for our region is 3.0 ACH50, not 5.0. Second, builders confuse total duct leakage with leakage to outside. 2024 IECC R403.3.5 caps leakage to outside at 4 CFM25 per 100 ft² of conditioned floor area when ducts run outside the envelope. Total leakage can run higher and still pass code, but NGBS-2023 §704.1 separately requires ducts to be sealed and tested.
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Call (859) 983-7382 Get a QuoteThe standard requires third-party verification at every tier per NGBS-2023 §702.1.1. Verifier credentials must be an NGBS Green Certified Verifier, RESNET Certified HERS Rater, BPI Building Analyst, or an equivalent approved by Home Innovation Research Labs. Different compliance pathways impose different specifics; the verifier credential is not interchangeable across every chapter.
The point structure uses a weighted category system. A builder must hit a minimum number of points in each of the seven categories, Lot, Resource Efficiency, Energy Efficiency, Water Efficiency, Indoor Environmental Quality, Operation/Maintenance, and Education, plus a project total. HECS project data shows that Bronze projects typically land around the entry-tier point floor, while Emerald projects require net-zero energy performance and significantly higher point totals across every category.
Tier-specific mandatory practices are where projects fail certification. Indoor environmental quality requirements call out ASHRAE 62.2-2022 as the ventilation reference per NGBS-2023 §903. Energy Efficiency draws on the 2024 IECC for envelope and duct leakage. Resource Efficiency references ANSI/RESNET/ICC 850 or equivalent for duct leakage testing per NGBS-2023 §704.1.
HECS delivers NGBS Green verification for residential and multifamily projects across Kentucky, Indiana, Ohio, Tennessee, Illinois, and Missouri. We coordinate the verifier-of-record role with the builder's architect and HERS Rater when one is on the team. For a scope call: (859) 983-7382 or hecsusa.com/contact/.
The table below summarizes where each level diverges on the practices HECS tests most often. Exact point thresholds vary by category weight and should be confirmed against the published NGBS 2023 scorecard at the time of certification.
| Practice Area | Bronze | Silver | Gold | Emerald |
|---|---|---|---|---|
| Third-party verification | Required | Required | Required | Required |
| Air leakage target (typical KY/IN CZ 4A-5A) | 3.0 ACH50 | 3.0 ACH50 | 3.0 ACH50 | 3.0 ACH50 |
| Duct leakage to outside | Required | Required | Required | Required, tighter |
| Ventilation per ASHRAE 62.2-2022 | Required | Required | Required | Required |
| Energy performance baseline | Code minimum | Modest improvement | Substantial improvement | Net-zero verified |
| Multifamily sampling per ANSI/RESNET/ICC 380 | Allowed | Allowed | Allowed | Allowed with tighter pass criteria |
HECS verification work falls into three deliverables. First, the air-leakage and duct-leakage test report, blower door results expressed in ACH50 or CFM50, duct leakage to outside expressed in CFM25 per 100 ft², plus the retest after corrective work. Second, the ventilation compliance verification, confirming the mechanical ventilation system is sized to the ASHRAE 62.2-2022 §4.1 equation and that local exhaust meets §4.3 rates. Third, the photo-and-documentation file, air barrier photos at framing inspection, duct sealing photos at rough-in, and HVAC functional testing records.
The verifier submittal goes to Home Innovation Research Labs through the NGBS project portal. For multi-family projects, HECS applies the sampling protocol from ANSI/RESNET/ICC 380 when the builder elects sampling, sample sizes scale with building height and unit count. Builders pursuing ENERGY STAR MFNC v1.3 Rev05 alongside NGBS see the blower door and duct leakage results double-count for both programs. That coordination saves a retest cycle.
NGBS-2023 separates mandatory practices from point thresholds. A builder can rack up points in Energy Efficiency but fail Bronze if the air-barrier inspection per 2024 IECC R402.4.1.1 is missing from the photo log. HECS treats the mandatory-practice checklist as a pre-test gate before any scoring begins, retesting a failed mandatory practice costs more than scheduling the right inspection on framing day.
Does NGBS 2023 require a HERS Rater at every tier? No. Per NGBS-2023 §702.1.1.1, the verifier credential can be an NGBS Green Certified Verifier, RESNET HERS Rater, BPI Building Analyst, or an equivalent approved by Home Innovation Research Labs. Specific compliance pathways may still require HERS credentials even when an NGBS verifier is on the project.
Can a builder mix sampling and unit-by-unit testing on the same multifamily project? Generally no, the sampling protocol under ANSI/RESNET/ICC 380 defines a single sampling rate per building. HECS recommends deciding the sampling strategy at design review, not after rough-in, because switching mid-project can invalidate prior test results.
Is NGBS Silver enough to access state housing finance agency incentives in Kentucky? HECS cannot speak to agency-specific program rules, but Kentucky Housing Corporation incentives typically reference certified programs by name rather than tier. Confirm with the agency before locking the certification target.
HECS provides NGBS Green verification, blower door testing, duct leakage testing, and HVAC testing and balancing for projects across Kentucky, Indiana, Ohio, Tennessee, Illinois, and Missouri. Our verifier-of-record scope covers single-family, duplex, and multifamily projects up to mid-rise. Reach the HECS team at (859) 983-7382 or [email protected]. To scope a project, start at hecsusa.com/contact/ or browse the full service catalog at hecsusa.com/services/. HECS also serves Louisville KY, Lexington KY, Cincinnati OH, Indianapolis IN, Nashville TN, and St. Louis MO. HECS is not the design engineer or installer, we test, balance, and certify.
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