InterNACHI Standards of Practice

Our moisture inspections follow InterNACHI Standards of Practice, using visual examination and moisture meters to detect water intrusion, humidity problems, leak damage, and conditions conducive to mold growth. We identify moisture sources and recommend corrective actions.

What We Inspect During Moisture Assessment

Visual Moisture Indicators

Water stains on ceilings, walls, and floors
Discoloration and paint bubbling
Mold or mildew growth
Efflorescence on foundations
Warped or buckled flooring
Musty odors indicating moisture
Condensation on windows and pipes
Rust and corrosion on metal
Damp or wet insulation

Common Moisture Entry Points

Roof leaks and damaged shingles
Failed window and door seals
Foundation cracks and seepage
Plumbing leaks (supply and drain)
HVAC condensate drainage
Poor exterior grading and drainage
Gutter and downspout issues
Bathroom and kitchen fixture leaks
Attic condensation and ventilation

Moisture Meter Testing

Suspicious areas identified visually
Areas with staining or discoloration
Below windows and doors
Around plumbing fixtures
Near HVAC equipment
Foundation walls and floors
Areas with visible mold
Recently repaired or painted areas

High-Risk Areas We Examine

Bathrooms (showers, tubs, toilets)
Kitchens (sinks, dishwashers)
Laundry rooms (washers, dryers)
Basements and crawl spaces
Attics and roof spaces
Below-grade areas
Around water heaters and HVAC
Window and door perimeters

Humidity & Ventilation

Relative humidity levels (should be 30-50%)
Bathroom exhaust fan operation
Kitchen exhaust venting
Crawl space ventilation/encapsulation
Attic ventilation adequacy
Dehumidifier presence and operation
Signs of condensation problems

Common Moisture Problems in Minnesota

Basement Water Seepage

Minnesota's wet springs and clay soils cause basement moisture, seepage, and flooding. We identify water entry points, grading issues, and drainage problems requiring correction.

Ice Dam Water Damage

Winter ice dams force water under shingles, causing ceiling stains, wall damage, and insulation saturation. We identify ice dam damage patterns and contributing factors.

Attic Condensation & Frost

Warm, humid air entering cold attics causes condensation, frost buildup, and mold growth. We identify moisture sources, ventilation inadequacies, and air leakage.

Crawl Space Moisture

Damp crawl spaces from ground moisture, poor drainage, or inadequate ventilation cause mold, rot, and structural damage. Encapsulation often necessary.

Plumbing Leaks

Slow leaks under sinks, toilets, and behind walls cause hidden damage, mold growth, and structural deterioration. We identify active leaks and past damage.

Window Condensation

Excessive indoor humidity or failed window seals cause condensation, frame rot, and mold. We identify causes and recommend humidity control or window replacement.

🚩 Critical Red Flags We Look For

Active Water Leaks: Currently leaking pipes, roofs, or foundations
Extensive Mold Growth: Large areas of visible mold indicating chronic moisture
Structural Wood Rot: Moisture-damaged framing, joists, or support members
Basement Flooding Evidence: Water lines, silt deposits, or recent flooding
High Moisture Readings: Moisture meter readings indicating active problems
Sewage Backup: Evidence of sewage or contaminated water intrusion
HVAC Condensate Flooding: Failed AC or furnace drainage causing water damage
Hidden Damage: Moisture behind walls or under floors not visible until testing

Moisture Control Tips for Minnesota Homeowners

Maintain Proper Grading: Slope soil away from foundation on all sides
Clean Gutters and Extend Downspouts: Direct water 6+ feet from foundation
Use Bathroom Fans: Run exhaust fans during and 20 minutes after showers
Control Indoor Humidity: Keep relative humidity between 30-50% year-round
Fix Leaks Immediately: Address plumbing, roof, and foundation leaks promptly
Improve Attic Ventilation: Ensure adequate soffit and ridge venting
Seal Air Leaks: Caulk and weatherstrip to prevent moisture infiltration
Monitor Basement Humidity: Use dehumidifiers to keep basements dry

Frequently Asked Questions

How do moisture meters work?

We use pin-type and pinless moisture meters that detect moisture content in building materials. Pin meters penetrate surfaces to measure electrical resistance (higher moisture = lower resistance). Pinless meters use electromagnetic sensors to scan surfaces without damage. Readings help identify hidden moisture problems not visible to the eye.

What moisture level indicates a problem?

For wood framing, moisture content above 19% indicates excessive moisture and potential rot/mold risk. Readings of 12-15% are normal for Minnesota homes. For drywall and plaster, readings above 1% (on our scale) suggest moisture problems. We compare suspect areas to known dry areas for context.

Can you identify all moisture problems?

We identify visible moisture problems and test suspicious areas, but cannot see behind all walls, under all floors, or inside all cavities. Our inspection is visual and non-invasive. When concerns exist, we may recommend infrared thermography or invasive testing by moisture specialists.

Do you test for mold?

We identify visible mold growth and moisture conditions conducive to mold. We do not perform mold testing (air sampling or surface testing) as that requires specialized certifications and laboratory analysis. When mold is suspected or found, we recommend certified mold inspectors for testing and remediation specialists for removal.

What causes basement moisture in Minnesota?

Common causes include poor exterior grading, inadequate gutters/downspouts, foundation cracks, high water tables, hydrostatic pressure, and condensation. Minnesota's wet springs, clay soils, and frost action exacerbate basement moisture. Solutions include improving drainage, sealing cracks, installing sump pumps, and controlling humidity.

Serving Winthrop & Surrounding Communities

Winthrop, MN

Gaylord, MN

Lafayette, MN

New Ulm, MN

Gibbon, MN

Fairfax, MN

Sleepy Eye, MN

Springfield, MN

Glencoe, MN

Hutchinson, MN

Arlington, MN

Green Isle, MN

Brownton, MN

Stewart, MN

Bird Island, MN

Schedule Your Professional Moisture Inspection Today

InterNACHI-certified inspector serving Winthrop and surrounding areas

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💧 Moisture Inspection - What We Check