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Moisture & Structural Integrity

Nature-friendly

Site design supports pollinators, native ecology, dark skies, and habitat preservation.

Nature-friendly (placeholder seal) NF PLACEHOLDER

Description

The Nature-friendly badge recognizes projects whose site design actively supports the local ecology rather than displacing it. The badge sits in the Moisture & Site pillar because most of its strategies — native plantings, on-site stormwater handling, reduced site disturbance — also reduce moisture risk to the home.

Earning the badge requires meaningful work in three domains: plantings (native, pollinator-supporting, low-input), lighting (dark-sky-compliant), and habitat preservation or restoration. A token rain garden or a single pollinator strip will not qualify; the badge looks for a site-wide design approach.

Required standard requirements

To earn this badge, the project must meet all of the following existing GreenStar requirements:

Additional badge criteria

Beyond the required standard requirements above, the project must also satisfy:

Plantings

  1. 01.

    At least 60% of new vegetated area (by sq ft) planted with species native to the project's EPA Level III ecoregion, listed in a credible native-plant database (Lady Bird Johnson Wildflower Center, USDA PLANTS, regional native-plant society).

  2. 02.

    Pollinator support: at least three native species each from spring, summer, and fall bloom periods, providing continuous bloom from last frost to first frost.

  3. 03.

    No invasive species (per state invasive-species list) introduced or retained on the site.

  4. 04.

    Lawn area limited to ≤ 25% of vegetated area on lots under 1/2 acre, ≤ 15% on larger lots. Where lawn is included, drought-adapted turf mixes (microclover, fine fescue, buffalograss) preferred over Kentucky bluegrass in non-irrigated zones.

  5. 05.

    No use of neonicotinoid pesticides during installation or as part of the maintenance plan.

Dark-sky lighting

  1. 01.

    All exterior fixtures DarkSky-approved (formerly IDA) or equivalent fully-shielded, downcast design with 0 lumens above horizontal.

  2. 02.

    Color temperature ≤ 3000K (warmer is better; 2200K–2700K preferred). Blue-rich light disrupts wildlife and pollinators.

  3. 03.

    Motion-activated or scheduled control on all non-essential exterior lighting (path lighting may remain on for safety).

  4. 04.

    No upward-facing accent or landscape lighting.

Habitat preservation & restoration

  1. 01.

    Preserve existing mature trees (DBH ≥ 8 inches) — at least 75% retained on the project parcel, with tree-protection fencing during construction.

  2. 02.

    Limit site disturbance to within 5 ft of building footprint + utility/driveway corridors. Mass grading of the lot does not qualify.

  3. 03.

    At least one wildlife-supportive feature installed: nesting boxes appropriate to local species, brush-pile shelters, native wildflower meadow strip, or wetland-edge buffer.

  4. 04.

    Bird-strike mitigation on glazing > 4 sq ft within 30 ft of vegetation: ABC Bird-Smart-rated glass, applied film with ≥ 2x2 inch pattern density, or external screens.

Documentation

  1. 01.

    Landscape plan with plant list — botanical and common names, native/non-native flag, bloom period, and quantities.

  2. 02.

    Exterior lighting plan with fixture cut sheets showing DarkSky approval and color temperature.

  3. 03.

    Tree-protection plan with preserved trees marked on the site survey.

  4. 04.

    Photos at completion: pollinator plantings, lighting installation, preserved trees with protection markers, and any installed wildlife features.

Verification by tier

Evidence the project team submits at each certification tier. Cumulative — higher tiers include everything below unless noted otherwise.

  1. Certified

    Self-attestation
    • 01.

      Landscape plan with plant list (botanical name, common name, native flag, bloom period, quantity).

    • 02.

      Exterior lighting plan with DarkSky-approved fixture cut sheets and color-temperature spec.

  2. Silver

    Documents + photos
    • 01.

      Tree-protection plan with preserved trees marked on the site survey; pre-construction tree-protection-fencing photos.

    • 02.

      No-neonicotinoid certification from the landscape contractor or maintenance plan.

  3. Gold

    Third-party test
    • 01.

      On-site verification of installed plantings, lighting, and any wildlife features (nesting boxes, brush piles, meadow strip, bird-strike glazing) by an arborist or landscape architect.

  4. Platinum

    Post-occupancy verification
    • 01.

      12-month maintenance log confirming no neonicotinoid use and active management of any invasive species.

    • 02.

      Optional pollinator-count survey (community-science platform such as Bumble Bee Watch or Project Wingspan).

Energy & Climate Resilience Required from Certified Resilience Nature-friendly Walkability

Climate Risk Assessment

Determine the project's future climate risks using a climate-resource tool. Document and mitigate identified risks (stringency rises by tier).

Scope

Site-specific climate risks over the project's expected lifetime (typically 30-60 years), identified using a recognized climate-projection tool.

Requirements

Assessment + mitigation

  1. 01.

    Run the project address through a climate-risk tool such as NOAA's Climate Explorer, FEMA's National Risk Index, or the U.S. Climate Resilience Toolkit.

  2. 02.

    Identify the top risks for the project location — typical categories: extreme heat days, wildfire, riverine/coastal flooding, hurricane/severe wind, drought, freeze events.

  3. 03.

    Document a mitigation strategy for each identified risk. The stringency rises by tier: Certified must mitigate the highest risk; Silver and above must mitigate progressively more.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Climate-risk report exported from NOAA Climate Explorer, FEMA NRI, or equivalent tool, dated within 12 months of registration.

  2. 02.

    Mitigation plan listing each risk and the specific design or operational response (e.g. "high heat → install 200A panel for future heat-pump upgrade; specify R-21 walls").

Guidance

Why this is the first requirement

Climate risk drives many of the downstream Energy and Moisture decisions in this standard — sizing cooling for the higher peak days, hardening the envelope against wildfire, raising the foundation in flood-prone areas. Doing the assessment up front makes the rest of the certification easier to defend.

Tools

Example — A typical risk → mitigation chain

Project in central Texas: top risks come back as extreme heat (highest), drought (high), and severe wind/hail (high). Mitigation: oversized HVAC return + R-21 walls + cool roof for heat; xeriscape + rainwater catchment for drought; impact-rated windows + reinforced roof anchors for wind. Each mitigation aligns with a separate GreenStar requirement, so the climate report becomes the design narrative.

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Moisture & Structural Integrity Required from Certified Nature-friendly Storm Water Control

Moisture & Wall Water Leak Assessment

Inspect roof condition, flashing, gutters, siding, ground slope, basement moisture (meter), and visible mold/mildew. Repair findings.

Scope

The entire dwelling envelope and grounds — roof, flashing, gutters, siding, foundation, basement/crawlspace, around plumbing penetrations, and visible interior surfaces.

Requirements

Inspection checklist

  1. 01.

    Inspect roof condition: missing/damaged shingles, exposed nails, sealant failures around penetrations (vents, chimneys, skylights).

  2. 02.

    Inspect flashing: chimney, skylight, dormer, kickout/step flashing at roof-wall intersections.

  3. 03.

    Inspect siding: cracks, sealant failures around windows and doors, weep holes clear (for brick veneer).

  4. 04.

    Inspect ground slope around the foundation: must drop at least 6 inches over the first 10 feet (6% slope) away from the building.

  5. 05.

    Use a moisture meter on basement walls, crawlspace, and any area showing past water staining.

  6. 06.

    Visually inspect for active mold, mildew, or water staining throughout the dwelling.

  7. 07.

    Document any findings; address all active leaks or moisture issues before certification.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Inspector's moisture/leak assessment report with photos of each inspection point.

  2. 02.

    Moisture meter readings (basement, crawlspace, any wet area).

  3. 03.

    Repair documentation for any findings — receipts, photos, contractor sign-off.

Guidance

Why this is the most consequential single check

Water intrusion is the #1 cause of premature building failure. A small unaddressed roof or flashing leak can rot framing, feed mold, ruin insulation, and corrode metal connectors within 1-3 years. The full envelope inspection at certification catches these before they become structural.

Common findings + what they cost to fix

Failed kickout flashing at the roof-wall junction (~$200-$500 to repair, prevents thousands in wall rot). Clogged gutters or downspouts dumping water at the foundation ($100-$300 to clear/extend). Negative grade (soil sloping toward house) — $500-$2,000 to regrade.

Note

A moisture meter ($30-$100) gives quantitative readings. Pin meters insert into the material; pinless meters use electrical capacitance. For walls and trim, pinless is non-destructive and good for screening; pin meters give the most accurate reading at depth.

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Moisture & Structural Integrity Required from Certified Nature-friendly Storm Water Control

Functional Gutter System

Gutters drain water well away from the foundation — OR site has well-draining sandy soils verified per USDA classification.

Scope

Roof drainage system — gutters, downspouts, splash blocks, and the ground area where roof water terminates.

Requirements

Choose one path

  1. 01.

    Standard path: install gutters that fully capture roof runoff, with downspouts that discharge a minimum of 4 feet from the foundation (extended via splash blocks, underground drains, or extensions).

  2. 02.

    Soil exemption: site has well-draining sandy soils (USDA classification: sand, loamy sand, sandy loam) verified by a soil test or USDA Web Soil Survey lookup. In this case gutters are optional.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Photos of installed gutters + downspouts + termination points.

  2. 02.

    OR (soil exemption): USDA Web Soil Survey report for the project parcel showing eligible sandy soil classification.

Guidance

Why downspout extensions matter so much

A 1-inch rainfall on a 2000 sf roof produces 1,200 gallons of water. If that volume drops within 1 foot of the foundation, it saturates the soil there, raises hydrostatic pressure on the foundation wall, and over years pushes water into the basement. 4-foot downspout extensions are the single cheapest fix for basement leaks — $5-$30 per downspout.

Resources

Note

In tight urban sites where 4-foot extensions aren't feasible, underground PVC drain to a daylight termination or dry well is acceptable. Sump pump discharge does not count — that's water already inside the building.

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Moisture & Structural Integrity Required from Silver Nature-friendly Storm Water Control

Site Grading or French Drains

Grading slopes away from the home — or french drains are installed (new construction).

Scope

Site grading and subsurface drainage in new construction projects.

Requirements

Choose one path

  1. 01.

    Grading path: site must be graded to slope away from the foundation at a minimum of 6 inches over the first 10 feet (6% slope), continuing to drop at least 2% beyond that.

  2. 02.

    French drain path: where grading is constrained (urban sites, retaining walls, sloped lots), install a perimeter French drain at the foundation footing depth, connected to a daylight termination, dry well, or storm sewer.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Civil/grading plan stamped by the project engineer showing the slope profile.

  2. 02.

    OR French drain detail drawing + photos of installation before backfill.

Guidance

Why the 6/10 rule

IRC R401.3 specifies the 6"/10ft (6%) minimum positive grade away from foundations. Below that slope, surface water sheets toward the foundation during heavy rain and saturates the perimeter soil. Above 6%, the slope is steep enough that water consistently drains away even on saturated ground.

Note

On urban infill lots where positive grading is impossible (e.g. neighbor's lot drops toward yours), French drains combined with a sump pump (interior or exterior) become the only practical solution. Plan for the sump pump in the electrical load at the climate-risk assessment stage.

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