Water Damage and Moisture Intrusion Calculator
Estimate restoration costs, drying time, and damage severity for water-damaged areas based on affected square footage, water contamination category, and material types.
Formulas Used
Water Volume (gal): Area (ft²) × Depth (in) × 0.0833 (ft/in) × 7.48052 (gal/ft³)
Drying Time (days): BaseDaysclass × HumidityFactor × TempFactor
where HumidityFactor = 1 + max(0, RH − 60) / 100 | TempFactor = 1 + |T − 80°F| / 80
Severity Index (0–100): CategoryScore + ClassScore + (RH/100 × 15) + (min(depth,12)/12 × 10)
Mold Risk Score (0–100): max(0, (RH−60)/40 × 40) + max(0, (T−60)/60 × 20) + (min(days,14)/14 × 40)
Dehumidifier Capacity (pints/day): Area × 0.0007 × max(0, RH − 50) × (T / 70) [AHAM Standard]
Total Cost: Extraction + Remediation (Area × BaseCost/ft² × ClassMultiplier) + Equipment Rental + Flooring + Wall Repair + Antimicrobial
Assumptions & References
- Water damage categories (1–3) and classes (1–4) follow IICRC S500 Standard for Professional Water Damage Restoration.
- Base drying times: Class 1 = 2–3 days, Class 2 = 3–5 days, Class 3 = 5–7 days, Class 4 = 7–14 days (IICRC S500).
- Dehumidifier sizing uses the AHAM (Association of Home Appliance Manufacturers) formula with a 70-pint/day standard unit baseline.
- Air mover placement: 1 unit per 75 sq ft per IICRC best practices.
- Mold growth risk is elevated when RH > 60%, temperature > 60°F, and drying time exceeds 48 hours (EPA mold guidelines).
- Cost estimates are national averages (2024); actual costs vary by region, contractor, and extent of damage. Range shown is ±15–20%.
- Category 3 (Black Water) costs include mandatory antimicrobial treatment at $0.50/sq ft.
- Flooring replacement costs: Carpet $4.50/ft², Hardwood $12/ft², Laminate $6/ft², Tile $8/ft², Vinyl $5/ft² (installed).
- This calculator provides estimates only. A certified water damage restoration professional (IICRC-certified) should assess all significant water damage events.