Also in: Disaster Response and Recovery
Dehumidifier Sizing
Required pints per day by AHAM and field methods.
Example
You enter
- Room volume (ft³) 6000
- Water class 2
You get
- AHAM pints/day 120
- Field pints/day 120
- Recommendation 120
Checked against published worked examples from: IICRC S500 initial dehumidification factor chart (LGR).
Details, formula, and sources
Formula or tableRequired dehumidifier capacity (PPD = pints per day) sized from affected cubic feet, water class (1-4 per IICRC S500). Required AHAM pints per day = affected cubic feet / IICRC LGR factor (100 ft³ per pint for Class 1, 50 for Class 2, 40 for Classes 3 and 4). AHAM-rated capacity is the published rating at 80 °F / 60% RH; the IICRC chart is already the field recommendation in AHAM pints, so the field figure equals it.
Source and editionIICRC S500-2021 §10 (Equipment); AHAM DH-1-2008 (Dehumidifier rating standard) by name.
Free accessAHAM standards licensed; rating principles free at AHAM (aham.org) outreach.
What governsEstimate. AHJ and licensed professional govern.
API field namesroom_cubic_feet, water_class, aham_pints_per_day, field_pints_per_day, recommendation
- Field figure equal to the AHAM figure; no derate is appliedIICRC S500 LGR sizing chart