The calculator converts each input into an index from 0 to 100, then applies weights:
- Depth scales to 100 at 25 mm standing water.
- Duration scales to 100 at 24 hours exposure.
- Area uses affected/total area, adjusted for hidden spread using visible damage %.
- Contamination combines water type, source, mold odor, and response delay.
This is a decision-support tool. Always follow your local standards and site safety rules.
- Stop the source if it is safe to do so.
- Measure total area and map affected boundaries.
- Estimate peak depth and how long materials stayed wet.
- Record humidity, temperature, and contamination indicators.
- Click Calculate severity to get score and class.
- Use the CSV/PDF exports for documentation and handover.
| Scenario | Total (m²) | Affected (m²) | Depth (mm) | Duration (h) | Humidity (%) | Water type | Likely class |
|---|---|---|---|---|---|---|---|
| Small roof drip | 120 | 4 | 1 | 2 | 55 | Clean | Minor |
| Fixture leak to drywall | 250 | 18 | 6 | 8 | 72 | Gray | Moderate–Severe |
| Flooded ground floor | 600 | 260 | 30 | 20 | 85 | Flood | Critical |
Use measured site values to replace these examples.
Why severity scoring improves water-damage decisions
On active sites, water intrusion can look small while spreading through cavities, insulation, and joints. A structured severity score converts observations into comparable numbers, helping supervisors choose between monitoring, controlled drying, or full mitigation. This calculator combines depth, duration, area ratio, recurrence, humidity, material sensitivity, and contamination indicators to support consistent triage. Using repeatable scoring also improves communication with owners, insurers, and subcontractors, because the same inputs produce the same class and documented justification for every incident.
Interpreting depth, duration, and spread inputs
Depth and exposure duration are weighted heavily because they correlate with saturation and secondary damage. Area is scaled by affected-to-total ratio, then adjusted using visible damage percent to represent hidden spread. Lower visibility increases the effective risk because moisture may be behind finishes or under flooring. Rooms affected adds a small boost to reflect multi-zone complexity and additional labor.
Moisture environment and material vulnerability
Relative humidity slows evaporation and raises microbial risk, especially above 70%. Temperature impacts drying efficiency, with cooler conditions increasing the estimated drying days. Material sensitivity captures how porous assemblies respond: drywall and insulation can lose integrity quickly, while tile or masonry may tolerate brief wetting with proper drying and verification.
Contamination, delay, and health-driven escalation
Clean water typically needs rapid extraction and drying, but gray, black, and flood conditions require stricter controls. The contamination index also considers source type, mold odor, and response delay. Delays beyond the first day increase odor, staining, corrosion, and hidden microbial growth potential. When the score trends severe or critical, prioritize containment, safe removal of porous materials, and targeted dehumidification.
Reporting, exports, and operational handover
Documentation reduces dispute risk and helps coordinate trades. Use the CSV export for logs and the PDF for handover packages that include measured inputs, severity score, class, response guidance, and a transparent point breakdown. Recalculate after extraction, demolition, or drying milestones to show improving conditions, justify equipment changes, and support closeout decisions.
1) What does the severity score represent?
The score is a 0–100 weighted indicator of intrusion impact based on depth, duration, spread, environment, materials, and contamination. It helps standardize triage decisions across crews and shifts.
2) Why is visible damage percentage included?
Visible damage can understate actual wetting. Lower visibility increases the hidden-spread adjustment, reflecting moisture behind finishes or under floors that still requires mapping and drying verification.
3) Is the drying-time estimate a guarantee?
No. It is a planning estimate based on moisture load and conditions. Confirm progress with moisture readings and adjust equipment, ventilation, and material removal if drying stalls.
4) When should I treat an event as contamination risk?
Use higher-risk water types for sewage, floodwater, or unknown sources. Add “Yes” for mold odor when present. These inputs elevate the contamination index and often push response toward removal and containment.
5) How do recurring leaks affect results?
Events per year increases the frequency index, representing cumulative deterioration, repeated wetting cycles, and higher probability of hidden damage. Fix the source and reassess after repairs.
6) What should I do after I calculate a severe score?
Stop the source, extract water, and map moisture boundaries. Start aggressive drying and consider removing saturated porous materials. Document everything and use the PDF export for mitigation handover.