How to Dry Out a Wet Hardwood Floor

What to do when a hardwood floor gets wet from a leak or spill: shut off power, remove the water, dry it slowly with air movement and a dehumidifier, track it with a moisture meter, wait out cupping, and know when boards must be replaced.

By Patrick & Dylan · Florida Certified General Contractor, Lic. #CGC1541672

A wet wood floor doesn't have to be a lost floor. This guide pulls together advice from university extension services (North Dakota State, Texas A&M, UF/IFAS), FEMA and the American Red Cross, the EPA, the Maryland Historical Trust and the National Wood Flooring Association's magazine. It's written for clean-water leaks and spills. Floodwater and sewage are a different job (see the box below).

Stop and call a pro before you start if:

You'd have to stand in water to reach the electrical panel. FEMA and the Red Cross say to call an electrician in that case; the CDC says never to turn power on or off while standing in water.
The water was floodwater or sewage. The EPA says to call a professional if water or mold damage came from sewage or other contaminated water.
Mold covers more than about 10 square feet. The EPA points to its professional remediation guidance for areas that size. Florida's mold-licensing law exempts homeowners working on their own home (s. 468.841).
The home was built before 1978 and you'd be sanding. The EPA says older homes may have lead-based paint and recommends a lead-safe certified contractor.
You'd be disturbing vinyl tile, sheet flooring backing or old adhesives. The EPA lists these as places asbestos can be found and says not to sand or try to level asbestos flooring.
Our advice: if the floor feels soft, sags or bounces, stay off that area and have the framing checked.

What you'll need

Item	Why	Where to buy
Fans	Moving air across the floor (FEMA and Red Cross)	Home Depot · Lowe's
Dehumidifier	Pulling moisture out of a closed room (FEMA and Red Cross; NDSU)	Home Depot · Lowe's
Wood moisture meter	Knowing when the floor is actually dry (NDSU; Nebraska Extension)	Home Depot · Lowe's
Towels and a mop	Picking up surface water	Around the house
Gloves, goggles and an N-95 respirator	If you find mold (EPA)	Home Depot · Lowe's
Inexpensive humidity monitor	Keeping indoor humidity below 60% (EPA)	Home Depot · Lowe's

NDSU Extension notes you may be able to borrow or rent a moisture meter from a hardware store or lumberyard, and that rented commercial dehumidifiers remove three to four times more water than home models.

Step by step

Step 1: Make it safe

FEMA and the Red Cross say "Electricity and water don't mix," and that you can turn off the power yourself if you can reach the panel without going through or standing in water. Otherwise, call an electrician. Our advice: turn off the breaker for any outlets near the wet floor before you start.

Step 2: Stop the water

UF/IFAS says you "must find and eliminate the sources of the excess moisture," or moisture problems will keep coming back. Our advice: shut off the fixture's valve or the main water valve, and call a licensed plumbing contractor for a leaking pipe. Drying won't work while water keeps coming.

Step 3: Get the water up fast

NDSU Extension says to "Remove all water as soon as possible from your home. Also remove furnishings that are water soaked." The EPA says to dry water-damaged areas and items within 24 to 48 hours to prevent mold growth. Our advice: mop and towel up standing water, and move wet furniture and anything soaked to a dry area.

Step 4: Move air and control humidity

A metal floor fan on a light wood floor — Point fans across the wet area. Stock photo.

Fans: FEMA and the Red Cross say "Fans help move the air and dry out your home." NDSU says to circulate air over wet surfaces and face fans into corners and other hidden areas.
Dehumidifier: NDSU says to use dehumidifiers when outside humidity is high, and to shut windows and doors while they run.
Windows: NDSU and FEMA say to open up only when it's drier outside than inside, and to close up when outside humidity is higher, which is common in Florida.
A/C: Texas A&M Extension says to use the air conditioning, fans and a dehumidifier to speed drying if the utilities are on. FEMA and the Red Cross say not to use central air or the furnace blower if the ducts were under water.
Humidity target: the EPA recommends keeping indoor humidity below 60%, ideally 30 to 50%.

Step 5: Dry it slowly, not hot

NDSU Extension says "Wooden floors should be dried gradually. Sudden drying could cause cracking or splitting." UF/IFAS says "Wooden floors dry out slowly. Don't build fires to rush drying," and the EPA's remediation guide says to use caution when applying heat to hardwood floors. The sources differ on air conditioning and fans: the Maryland Historical Trust advises against using heating, air conditioning or other forced air to dry wood floors, because rapid drying "can promote cupping," while Texas A&M and FEMA recommend A/C, fans and dehumidifiers for drying a house in general. Our advice: dehumidify the room and keep air moving gently, but don't aim fans or heat straight at the floor for long periods.

Step 6: Help the subfloor dry, or call a pro to open it up

Loose wood floor planks lying in an empty room — Pulled boards waiting to go back down. Stock photo.

For badly soaked floors, NDSU and Texas A&M say removing a board every few feet reduces buckling caused by swelling. Texas A&M adds: "If boards are tongue-and-grooved, consult a carpenter or flooring professional," and Oklahoma State Extension says the same. If your home has a crawl space, FEMA and the Red Cross say air needs to circulate below the floor, and to remove any plastic sheets, vapor barriers or insulation from under a soaked floor. Crawl space work in a tight space is often best left to a pro.

Step 7: Track it with a moisture meter

Nebraska Extension says the moisture level of materials "cannot be determined by appearance or time spent drying." Take readings in the wet area and in an unaffected part of the same floor, and write them down with the date. A Hurricane Katrina recovery advisory (hosted by HUD) says wet materials are presumed dry when readings are within 5 percent of like materials in unaffected areas. The National Wood Flooring Association's magazine stresses relying on moisture readings, not on how the floor looks or feels.

Step 8: Wait out the cupping before you sand

Cupped boards have raised edges. The Maryland Historical Trust says floorboards "may begin to warp as they dry, but further drying may bring the boards back to their original shape," and the NWFA's quick guide says damage often dissipates "or even completely disappear[s] as the flooring dries out over time." The NWFA's magazine explains that sanding a cupped floor flat too soon leaves it crowned (higher in the middle) once the wood dries back to normal. NDSU says not to refinish until the floor is thoroughly dry.

Step 9: Decide what to keep and what to replace

An empty bedroom with a finished hardwood floor — The goal: a dry, flat floor. Stock photo.

Still uneven after it's dry: NDSU says to plane or sand floors level, and not to refinish until thoroughly dry.
Buckled: the NWFA's quick guide says a buckled wood floor needs replacement wherever it buckled, because the fasteners or adhesives no longer hold.
Badly warped: NDSU says badly warped hardwood floors usually can't be repaired.
Moldy: NDSU says "Badly molded wood must be replaced."
Swollen engineered wood or laminate: LSU AgCenter says it should be replaced.

How long it takes

Several weeks or more. NDSU says to be prepared to let floors dry "for several weeks," and UF/IFAS says drying a floor "may take weeks or even months."
Longer before refinishing. NDSU says refinishing should wait until moisture has dried from framing and between walls and floors, which "may take several months."
Faster with equipment. FEMA and the Red Cross note that contractors with large fans and dehumidifiers can dry out a house in a few days.

Stop and call a pro if you find:

Boards that stay buckled or pull loose after drying.
A soft, spongy or sagging spot, or dark, crumbling wood when a board comes up (our advice: have the framing checked).
Mold over about 10 square feet, or mold that keeps coming back (EPA).
Water that came from a flood, sewage or a source you can't stop.
Moisture readings that won't come down after a few weeks.

Frequently asked questions

Can a water-damaged hardwood floor be saved?

Often, yes. The Maryland Historical Trust says further drying may bring boards back to their original shape, and LSU AgCenter says solid wood flooring can usually recover from flooding. Buckled, badly warped or moldy boards need replacing.

How long does a wet hardwood floor take to dry?

Several weeks or more. NDSU Extension says to be prepared for several weeks of drying, and refinishing may need to wait several months while the framing dries.

Should I sand a cupped floor right away?

No. The National Wood Flooring Association's magazine explains that sanding a cupped floor before it dries leaves it crowned later. NDSU says not to refinish until the floor is thoroughly dry.

Should I use heat to dry a wood floor faster?

No. NDSU Extension says sudden drying can cause cracking or splitting, and UF/IFAS says not to build fires to rush drying. Dehumidify and keep air moving gently.

Sources

General information, not legal, insurance or engineering advice. Rules change and vary by city; confirm with your building department, DBPR, your insurer, an attorney or an engineer as fits.

How to dry out a wet hardwood floor (and know when it needs a pro)