Sizing summary. A portable dehumidifier for a space under 2,000 sq ft should be rated 10–45 pints/day on the DOE 2019 scale, depending on three inputs: space type, square footage and moisture condition. Above-grade rooms need the least (10 pints/day for a slightly damp 500 sq ft room, 32 for a wet 2,000 sq ft room). Basements need more (12 to 40 pints/day) because moisture enters through the slab and walls. Crawl spaces need the most (12 to 45 pints/day) because they are exposed to soil moisture and outdoor air. Retail units come in 22, 35, 50 and 70-pint classes, so round up to the next class. All figures are modeled from the ENERGY STAR capacity bands (20–30, 25–40 and 30–50 pints/day for slightly damp, very damp and wet spaces) and the DOE Appendix X1 test at 65°F. Last verified 2026-09-08.
This guide turns DOE/ENERGY STAR capacity bands and public manufacturer charts into concrete pint/day recommendations by space type, square footage, and moisture conditions.
How to use: Pick your space type, estimate square footage, select the moisture condition that best matches reality, then round up to the next common class (22/35/50/70 pints). Basements and crawl spaces often benefit from sizing up one class. Prefer to have it done for you? Use the pint capacity picker.
Orientation bands based on public ENERGY STAR guidance. Always round up for cooler below‑grade spaces.
Basement
Slightly–Moderately damp (50–75% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
12 pints/day
22–35‑pint class
1,000 sq ft
18 pints/day
35‑pint class
1,500 sq ft
22 pints/day
35‑pint class
2,000 sq ft
26 pints/day
35–50‑pint class
Very damp (75–90% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
14 pints/day
22–35‑pint class
1,000 sq ft
22 pints/day
35‑pint class
1,500 sq ft
26 pints/day
35–50‑pint class
2,000 sq ft
32 pints/day
50‑pint class
Wet (90–100% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
16 pints/day
35‑pint class
1,000 sq ft
30 pints/day
50‑pint class
1,500 sq ft
35 pints/day
50‑pint class
2,000 sq ft
40 pints/day
50–70‑pint class
Crawl
Slightly–Moderately damp (50–75% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
12 pints/day
22–35‑pint class
1,000 sq ft
18 pints/day
35‑pint class
1,500 sq ft
22 pints/day
35‑pint class
2,000 sq ft
26 pints/day
35–50‑pint class
Very damp (75–90% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
16 pints/day
35‑pint class
1,000 sq ft
24 pints/day
35–50‑pint class
1,500 sq ft
28 pints/day
35–50‑pint class
2,000 sq ft
35 pints/day
50‑pint class
Wet (90–100% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
22 pints/day
35–50‑pint class
1,000 sq ft
32 pints/day
50‑pint class
1,500 sq ft
40 pints/day
50–70‑pint class
2,000 sq ft
45 pints/day
50–70‑pint class
Above-grade Room
Slightly–Moderately damp (50–75% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
10 pints/day
22‑pint class
1,000 sq ft
14 pints/day
22–35‑pint class
1,500 sq ft
18 pints/day
35‑pint class
2,000 sq ft
22 pints/day
35‑pint class
Very damp (75–90% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
12 pints/day
22‑pint class
1,000 sq ft
17 pints/day
35‑pint class
1,500 sq ft
22 pints/day
35‑pint class
2,000 sq ft
27 pints/day
35–50‑pint class
Wet (90–100% RH)
Square footage
Recommended capacity
Retail class
500 sq ft
14 pints/day
22–35‑pint class
1,000 sq ft
20 pints/day
35‑pint class
1,500 sq ft
26 pints/day
35–50‑pint class
2,000 sq ft
32 pints/day
50‑pint class
Whole‑home (ducted)
Whole‑home dehumidifiers are sized by moisture load, not square footage alone. As a rough orientation, manufacturer guidance places models in the 70–130 pints/day class serving roughly 2,000–4,000 sq ft depending on envelope tightness and climate. Always match against the published performance table at your design condition (e.g., 73°F / 60% RH per DOE; basements often operate cooler/drier).
Anchored to ENERGY STAR capacity bands for portable units under ~2,000 sq ft (20–30 pints/day for slightly/moderately damp, 25–40 for very damp, 30–50 for wet).
Square‑foot breakpoints follow legacy AHAM room‑size ladders, adjusted for modern DOE 2019 rating context.
Basements and crawl spaces are biased to the top of each band to reflect persistent moisture load through the envelope.
Whole‑home/ducted equipment should be matched against manufacturer submittals at the design condition (e.g., 73°F / 60% RH) or via Manual J/S latent load calcs.
Assumptions
Portable units sized for spaces up to ~2,000 sq ft; larger spaces should plan for multiple units or whole‑home equipment.
Basements and crawl spaces are biased toward the upper end of ENERGY STAR capacity bands due to persistent moisture load.
Square‑foot breakpoints chosen at 500/1000/1500/2000 to match common retail size classes and legacy room‑size ladders.
Recommendations are DOE 2019+ pint/day classes for shopping; actual daily extraction will be lower in cooler/drier air.
Whole‑home sizing should be matched to manufacturer submittals at the design condition or via Manual J/S latent load.
