Calculator Inputs
White theme • Responsive gridEnter site conditions and equipment to estimate drying duration. This tool supports quick planning, not a substitute for moisture-meter verification.
Example Data Table
These scenarios show typical inputs and outcomes. Your site conditions can shift results materially, especially humidity and extraction quality.
| Scenario | Area (m²) | Temp / RH | Wetness | Fans | Dehum (L/day) | Estimated time (hours) |
|---|---|---|---|---|---|---|
| Light spill cleanup | 12 | 24°C / 45% | Damp | 1 | 20 | ~10–18 |
| Room flood with extraction | 20 | 22°C / 55% | Wet | 3 | 30 | ~22–40 |
| Soaked carpet, high humidity | 28 | 20°C / 80% | Soaked | 4 | 50 | ~55–90 |
| Commercial loop, strong drying setup | 35 | 28°C / 40% | Wet | 6 | 90 | ~18–34 |
Formula Used
The calculator estimates retained water and divides it by an estimated removal rate. It then applies material, contamination, and buffer adjustments.
EvapRate = Area × 0.03 × VPDIndex × AirflowFactor
DehumRate = (DehumLpd / 24) × 0.70 × DehumEnv
How to Use This Calculator
- Measure room length and width, or enter total area directly.
- Select carpet and underlay types to reflect site materials.
- Choose wetness and water type; contamination affects time and safety.
- Enter temperature and humidity where drying will occur.
- Add equipment details: air movers, air changes, and dehumidification capacity.
- Apply a safety buffer if underlay or subfloor conditions are uncertain.
- Press Calculate to view results above the form.
- Export the result as CSV or PDF for reports and handovers.
Moisture Load and Material Retention
Drying time starts with how much water is held in the carpet system. Low‑pile synthetic floors often retain about 1.4 L/m², while dense wool or high‑pile materials can exceed 2.8–3.2 L/m². Underlay adds hidden moisture; a foam pad commonly contributes ~0.8 L/m², and thick felt pads can add ~1.1 L/m². Extraction reduces the retained load, but incomplete passes can leave significant water trapped at the backing and pad interface.
Airflow and Boundary Layer Control
Air movers accelerate evaporation by disrupting the boundary layer on fibers. A practical planning density is one air mover per 10–15 m², with tighter spacing for soaked carpet or pad. Aim for sweeping airflow across the surface, not direct “blasts” into corners. Repositioning fans every 8–12 hours can improve uniformity and reduce localized damp zones.
Humidity, Temperature, and Drying Potential
Temperature and relative humidity set the drying potential. At 24°C and 45% RH, evaporation is typically far faster than at 20°C and 80% RH. In high humidity, dehumidification becomes the primary driver. Keeping indoor RH closer to 40–55% and temperature above 20°C is a common target for stable, predictable drying cycles.
Equipment Planning for Restoration Timelines
Dehumidifier ratings are “best case” at specific conditions. As RH drops, removal usually declines, so plan with margin. For wet carpet, a working rule is roughly 1.5 L/day per m² of affected area, scaled up for contaminated water or heavy pads. Ventilation and HVAC mixing can improve consistency when outdoor air is not excessively humid.
Quality Control and Reoccupation Criteria
Use the estimate to schedule labor, but validate with moisture readings. Confirm carpet backing, pad, and subfloor are dry before reinstalling tack strips, replacing baseboards, or reopening occupied areas. If drying exceeds 48 hours, odor and microbial risk increases; adjust equipment, increase extraction, or consider controlled removal of the pad to protect finishes and indoor air quality.
| Example data | Value |
|---|---|
| Area | 25 m² |
| Carpet / Underlay | Medium pile synthetic + foam pad |
| Wetness / Water type | Wet / Clean |
| Extraction | Portable extraction |
| Conditions | 24°C, 50% RH |
| Air movers / ACH | 4 fans / 2.0 ACH |
| Dehumidification | 50 L/day |
| Typical estimated drying window | ~24–42 hours |
FAQs
1) Is this drying time a guarantee?
No. It is a planning estimate based on inputs and typical performance. Always verify carpet, pad, and subfloor dryness using moisture readings before reinstallation or occupancy.
2) Why does humidity change the result so much?
High relative humidity reduces evaporation and lowers dehumidifier effectiveness. Lowering RH to around 40–55% increases the moisture gradient, improving drying speed and consistency.
3) How many air movers should I use?
A practical planning target is one air mover per 10–15 m². Soaked carpet, thick pads, or limited ventilation usually benefit from tighter spacing and periodic fan repositioning.
4) What if the carpet was soaked for many hours?
Longer dwell time increases pad saturation and wicking into the subfloor. Increase extraction, add dehumidification, and consider lifting edges or removing pad if drying stalls or odor develops.
5) Does clean vs contaminated water affect drying time?
Yes. Contaminated water often requires extra cleaning steps, controlled removal, and higher safety margins. The calculator applies time multipliers, but remediation requirements may drive decisions beyond drying.
6) How do I enter dehumidifier capacity correctly?
Use the unit’s liters-per-day rating closest to your site conditions. If uncertain, use a conservative value and include a safety buffer, since performance typically drops as RH decreases.
7) When should I stop drying and reinstall?
Stop when moisture measurements indicate dry backing, pad, and subfloor. Visual dryness can be misleading, especially with underlay. Document readings for handover and quality control.