iDry Columbus
Dehumidifier Size Calculator
Dehumidifier & Air-Mover Sizing Calculator
Find the right dehumidifier capacity for your space — or size restoration equipment by water-loss class. Free, no signup.
Pick your mode
Your space
Room / area size
sq ft
How damp is it?
Recommendation
Bigger loss than a rental unit can handle?
iDry Columbus brings commercial LGR dehumidifiers and metered drying across Central Ohio.
Call / Text 614-810-0000Homeowner sizing follows AHAM 2019 capacity guidance; restoration sizing follows IICRC S500 dehumidification and air-mover principles. These are planning estimates — real equipment loads depend on temperature, vapor pressure, materials, and containment. For an active water loss, a professional should set and monitor the drying.
Dehumidifier sizing — frequently asked questions
What size dehumidifier do I need?
It depends on the area and how damp it is. As a rule, a slightly damp 500 sq ft space needs about a 20-pint unit, a damp 1,000 sq ft space a 30–35 pint unit, and a wet basement or a space after a leak a 50–70 pint unit. This calculator gives a pint-per-day figure for your exact size and dampness.
What size dehumidifier for a 1,500 sq ft basement?
A 1,500 sq ft basement that is damp typically needs roughly 35–50 pints per day; if it's very damp or recovering from water intrusion, step up to a 50–70 pint unit and run it continuously. Cold basements remove less than the label rating, so sizing up helps.
Is it better to undersize or oversize a dehumidifier?
Slightly oversize. An undersized unit runs constantly and never reaches the target humidity; a right-sized or slightly larger unit reaches it faster and cycles efficiently. After water damage, professionals deliberately oversize with LGR dehumidifiers to dry quickly before mold starts.
Will a dehumidifier dry out water damage by itself?
Not on its own. Dehumidifiers remove moisture from the air, but you also need air movers to pull moisture out of wet materials, and the wet materials and standing water dealt with first. Pro mode sizes both the dehumidification and the number of air movers for an active loss.
How many air movers do I need per room?
A common rule is about one air mover per 10–16 linear feet of wall, plus one for each inside corner or offset, with extra units for saturated or Class 3/4 losses. Pro mode calculates this from your room dimensions and water-loss class.