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Tier
Project

Pillar 4

Moisture & Structural Integrity

Keep water out of the building envelope and shed it correctly at the site. Covers moisture assessments, gutter and grading systems, certified wet-area assemblies, and duct quality.

7 requirements · 2 badges

Requirements

Grouped by the tier at which they first become mandatory. Tap any row to slide in the full detail.

Certified (2)

  • Moisture & Wall Water Leak Assessment

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

    Open

  • Functional Gutter System

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

    Open

Silver (4)

  • Site Grading or French Drains

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

    Open

  • No New Ducts Panned in Joists

    No newly installed ducts are panned in floor joists — they must be fully ducted to prevent unintended air paths.

    Open

  • Moisture-Resistant Flooring in Wet Areas

    Bathrooms, kitchens, main entryways, and laundry rooms use moisture-resistant flooring.

    Open

  • Certified Shower/Tub Surrounds

    New shower/tub surrounds use ASTM D3273-certified wallboard, certified coating, or drywall-free construction.

    Open

Platinum (1)

  • All Ducts Fully Ducted

    All HVAC ducts are fully ducted — none panned in joists.

    Open

Badges in this pillar

  • Nature-friendly

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

    Open

  • Storm Water Control

    Site retains, infiltrates, or treats stormwater on-site — rain gardens, permeable surfaces, cisterns.

    Open
Moisture & Structural Integrity Required from Certified

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

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

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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Moisture & Structural Integrity Required from Silver

No New Ducts Panned in Joists

No newly installed ducts are panned in floor joists — they must be fully ducted to prevent unintended air paths.

Scope

Newly installed HVAC return-air ductwork in new construction.

Requirements

  1. 01.

    No new HVAC return-air ducts may be "panned" — using the cavity between floor joists, capped with sheet metal, as the duct.

  2. 02.

    All return-air ductwork must be fully ducted (rigid metal or insulated flex), sealed at every joint with UL-181 rated mastic or tape.

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Photos of installed return-air ducts showing rigid or flex construction with sealed joints.

  2. 02.

    Marked-up mechanical plan confirming no panned joist bays.

Guidance

Why panned joists fail

A panned joist bay relies on the floor framing as the duct surface — which means every gap in the framing (around nails, knockouts, end joints, plumbing penetrations) becomes a leak. Field studies consistently find 20-40% air leakage in panned-joist returns, which directly degrades HVAC efficiency and creates pressure imbalances that drive pollutants into the house from the basement/crawlspace.

Note

Existing panned-joist returns in renovation projects are not required to be removed — this Silver requirement applies to new ductwork only. At Platinum, all ducts (new + existing) must be fully ducted.

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Moisture & Structural Integrity Required from Silver

Moisture-Resistant Flooring in Wet Areas

Bathrooms, kitchens, main entryways, and laundry rooms use moisture-resistant flooring.

Scope

Floor finishes in wet areas: bathrooms, kitchens, main entryways, and laundry rooms.

Requirements

  1. 01.

    Install moisture-resistant flooring in all wet-area rooms: tile, sheet vinyl, LVT/LVP, sealed concrete, or marine-grade plywood with appropriate finish.

  2. 02.

    Carpet, unsealed wood, and laminate flooring are not permitted in wet-area rooms.

  3. 03.

    Transitions between wet-area and dry-area flooring must include a watertight seal (caulk or threshold).

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Photos of installed flooring in each wet-area room.

  2. 02.

    Material spec sheets confirming moisture-resistant rating.

Guidance

Engineered wood + LVP — the modern wet-area workhorses

Luxury vinyl plank (LVP) and waterproof engineered wood are both visually indistinguishable from real hardwood at typical viewing distance and fully waterproof. They've become the default for kitchens and bathrooms in green-built homes. Look for products with a wear layer of 20+ mil and a real waterproof core (SPC or WPC).

Note

Tile remains the gold standard for showers and high-splash areas. For radiant heating systems, tile + a decoupling membrane (Schluter Ditra, etc.) prevents cracking from substrate movement.

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Moisture & Structural Integrity Required from Silver

Certified Shower/Tub Surrounds

New shower/tub surrounds use ASTM D3273-certified wallboard, certified coating, or drywall-free construction.

Scope

Wall surfaces inside shower and bathtub surrounds — the wet zones behind tile, panels, or solid surface.

Requirements

Choose one substrate path

  1. 01.

    Tile path: substrate must be ASTM D3273-certified mold-resistant cement board (e.g. Hardiebacker, Durock) or equivalent, or a waterproof membrane system over standard substrate.

  2. 02.

    Coating path: apply a certified waterproofing membrane (Schluter Kerdi, RedGard, Hydroban) over the entire wet-zone substrate before finish.

  3. 03.

    Drywall-free path: install a one-piece fiberglass, acrylic, or solid-surface shower/tub surround unit (eliminates wet-zone seams entirely).

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Substrate or coating product spec sheet with ASTM D3273 (mold resistance) or ANSI A118.10 (waterproofing) certification.

  2. 02.

    Photo of substrate installation BEFORE tile/finish (so the inspector can verify the substrate type).

  3. 03.

    OR photo of one-piece surround installation.

Guidance

Why standard drywall fails in showers

Even moisture-resistant ("green board") drywall is not waterproof — moisture eventually wicks through grout lines, saturates the gypsum core, and creates mold inside the wall cavity. Cement board (water-tolerant but not waterproof) plus a waterproofing membrane is the modern standard. One-piece surrounds eliminate the seam-failure risk entirely.

Resources

  • TCNA Handbook for Ceramic, Glass, and Stone Tile Installation

    Industry reference for shower wet-zone construction. Methods W245 (membrane) and B415 (tile over backer board with topical waterproofing) are the most common compliance paths.

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Moisture & Structural Integrity Required from Platinum

All Ducts Fully Ducted

All HVAC ducts are fully ducted — none panned in joists.

Scope

All HVAC supply and return ductwork in the dwelling — new and existing.

Requirements

  1. 01.

    Every duct in the HVAC system must be fully ducted (rigid metal or insulated flex). No panned joist returns, building-cavity returns, or wall-stud-bay supplies.

  2. 02.

    All duct joints sealed with UL-181 rated mastic or tape.

  3. 03.

    Duct leakage test must show ≤ 4 CFM25 per 100 sf of conditioned floor area (or stricter local code).

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Duct leakage test report from a certified tester showing total system leakage in CFM25.

  2. 02.

    Photos of representative duct runs showing all-rigid or all-flex construction.

  3. 03.

    For renovation: marked-up plan showing replaced/rebuilt ducts where panned cavities were removed.

Guidance

Why this is Platinum-only

Retrofitting fully-ducted returns in an existing house with panned-joist returns is invasive — typically requires removing some ceiling drywall to install new round flex. New construction is straightforward. Platinum tier reflects the level of envelope discipline required to actually achieve this end-state.

Resources

  • ASHRAE 152 — Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems

    The protocol behind duct leakage testing.

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Moisture & Structural Integrity

Nature-friendly

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

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:

Additional badge criteria

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.

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Moisture & Structural Integrity

Storm Water Control

Site retains, infiltrates, or treats stormwater on-site — rain gardens, permeable surfaces, cisterns.

Description

The Storm Water Control badge recognizes projects that retain, infiltrate, or treat stormwater on-site rather than discharging it to the municipal storm sewer. The badge sits within the Moisture pillar because effective stormwater control protects the home's foundation and the surrounding site equally — the same rain that erodes a slope is the rain that ends up in a basement.

Earning the badge requires moving meaningfully beyond the Moisture-pillar baseline of gutters and grading: green infrastructure (rain gardens, bioswales, dry wells), permeable surfaces, and/or cisterns sized to capture the design storm. The result is an improved water balance — more infiltration into the local water table, less peak flow into the storm sewer, less downstream flood risk.

Required standard requirements

To earn this badge, the project must meet:

Additional badge criteria

Design storm capture

  1. 01.

    Site is designed to retain or infiltrate the first 1 inch of rainfall on impervious surfaces — captured volume calculated as: (impervious area in sq ft × 1 inch ÷ 12) ÷ 7.48 = required storage in gallons.

  2. 02.

    OR the project meets the local stormwater management ordinance's "green infrastructure first" or "low impact development" pathway, whichever is more stringent.

  3. 03.

    Existing-home renovation pathway: at least 50% reduction in net stormwater discharge from the site, measured pre/post by impervious-area change or modeled in a tool such as EPA's National Stormwater Calculator.

Acceptable practices

  1. 01.

    Bioretention / rain gardens sized at ~5–10% of contributing impervious area, with native plants suited to alternating wet/dry conditions.

  2. 02.

    Permeable paving (pavers, porous concrete, porous asphalt) on driveways, patios, and walkways — counted as pervious in the design-storm calculation.

  3. 03.

    Rainwater cisterns (above- or below-grade) sized for the design storm and either irrigation-discharged or used for non-potable indoor uses (toilet flushing, laundry — local code dependent).

  4. 04.

    Dry wells or infiltration trenches for downspout discharge, sized using local infiltration rate (perc test required where soils are clay-heavy).

  5. 05.

    Vegetated swales, dry creek beds, and stepped check-dams where slope and area permit.

  6. 06.

    Green roofs or roof gardens — counted as impervious area reduction equal to the modeled retention coefficient (typically 0.4–0.7).

Site-specific requirements

  1. 01.

    No discharge of captured stormwater within 10 ft of the foundation or onto adjacent properties.

  2. 02.

    Sediment forebay or pre-treatment required for cisterns and infiltration features receiving runoff from parking or driveway surfaces.

  3. 03.

    Where greywater or rainwater is reused indoors, system must meet the same plumbing-code requirements as for the Zero Water Capable badge.

Documentation

  1. 01.

    Stormwater management plan showing impervious areas, drainage paths, design-storm calculation, and each retention/infiltration feature with sizing.

  2. 02.

    EPA National Stormwater Calculator output (or equivalent local model) showing pre- and post-development runoff volumes.

  3. 03.

    Soil infiltration / percolation test results for sites relying on dry wells or infiltration trenches.

  4. 04.

    As-built photos of installed features at completion.

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