Water Damage to Hardwood Floors and Laminate: What Can Be Saved

Water damage to hardwood floors is often repairable if you remove the water fast and dry the floor slowly and completely: mild cupping can flatten again as the wood dries, and stained or cupped boards can often be sanded and refinished afterward. Laminate is different. Once its fiberboard core swells, it does not shrink back, so swollen laminate planks are replaced. Either way, the subfloor underneath decides how much has to come up.

How water damages wood and laminate floors

Wood is hygroscopic: it takes on moisture from water and humid air and gives it back as it dries. The USDA Forest Products Laboratory's Wood Handbook explains that wood swells as it gains moisture and shrinks as it loses it, that it moves most across the grain, and that the surface dries before the core. That uneven movement is what makes floorboards change shape.

The common shapes of wood floor water damage:

The National Wood Flooring Association describes cupping as occurring across the width of the floorboard, with edges raised and centers lower, and says it happens when floors gain moisture.

Hardwood vs engineered vs laminate vs vinyl

Not every "wood-look" floor responds to water the same way.

Many laminate products are sold as water-resistant, which usually means they resist spills for a period of time, not standing water. Check your product's warranty, since some exclude water damage.

What to do in the first 24 hours

1. Stop the water at the fixture or main valve, and fix the source.
2. Make it safe. If water reached outlets, cords or appliances, turn off power to that area at the breaker, and don't stand in water while doing it. The Electrical Safety Foundation recommends having water-damaged electrical equipment evaluated by a qualified electrician.
3. Remove standing water now. Use a wet/dry vacuum or a floor water extractor, then towels. Don't let water sit; it keeps soaking into seams and the subfloor.
4. Clear the floor. Move furniture and rugs off the floor so it can dry and so nothing traps moisture against the wood.
5. Dry gently and steadily. The EPA's water damage table says for wood surfaces, remove moisture immediately and use dehumidifiers, gentle heat, and fans, and to use caution when applying heat to hardwood floors. Fast, hot drying can crack boards and dry the top before the bottom.
6. Dry the space below, too. If there is a basement or crawl space under the floor, it needs airflow and dehumidification as well.
7. Photograph everything for your insurance claim before removing anything.

The EPA's general guidance is to dry water-damaged areas and items within 24 to 48 hours to prevent mold growth. For a full overview, see what to do after water damage and how professional water damage restoration handles floors.

Will a wet wood floor go back to normal?

Often, partly or fully, if it is dried in time. As the underside dries and shrinks back, mild cupping can flatten on its own. Floors that stayed wet a long time, or that were soaked from below by a flooded basement or crawl space, are more likely to keep some cupping, gaps or stains.

The mistake to avoid is sanding too soon. If a cupped floor is sanded flat while the bottom of each board is still wet, the edges shrink as they finish drying and the floor ends up crowned. Wait until moisture readings in the floor and subfloor are back to normal for your home, then decide on sanding. A flooring professional can take readings with a moisture meter and compare them with an unaffected area.

How to fix water damage on a wood floor

What you can do depends on the damage:

• Light surface spots (white haze): Usually moisture trapped in the finish, not the wood. These often fade or can be handled with refinishing products made for that finish.
• Dark stains: Water has gone into the wood. Sanding may lighten them; deep stains often mean replacing individual boards.
• Mild cupping: Dry first, wait, then reassess. Many floors settle down without sanding.
• Lasting cupping or crowning after drying: Sand and refinish once moisture is back to normal.
• Buckling, rot or soft spots: Remove and replace the affected boards and check the subfloor.

Solid hardwood can be sanded several times over its life. Engineered wood has a thin top layer, so it may only tolerate a light sanding or none.

Laminate floor water damage repair

Laminate has no sand-and-refinish option. Swollen edges and peaked seams are permanent. If only a few planks are affected and the subfloor is dry, those planks can be swapped out, usually by unclicking the floor from the nearest wall. Keep leftover planks from installation for this. If water spread under a large area, the floor typically has to come up so the subfloor and underlayment can dry, or mold can grow underneath.

Water damage to subfloor

The subfloor is the plywood, OSB or particleboard deck the finished floor sits on. It is often the deciding factor in whether a repair stays fixed.

• Plywood can often be dried and reused. North Carolina State Extension notes that plywood can be dried and reused, while particleboard swells and disintegrates after a few days of wetness and must be replaced.
• OSB swells at the edges when wet; swollen panels may need replacement to keep the floor flat.
• Signs of a subfloor problem: soft or spongy spots, a musty smell, boards that keep cupping after the surface dries, or visible mold from below in a basement or crawl space.

Fixing subfloor water damage means drying it fully, replacing swollen or soft sections, and checking joists below. To fix bathroom floor water damage, also check the toilet wax ring, supply line and shower or tub edges, which often leak slowly into the subfloor for months.

If the wood stayed wet and smells musty, see our guide to mold on carpet and wood, and our drying out water damage guide for how professional drying works.

Basement floor flooding and floors over crawl spaces

Wood floors over a basement or crawl space can be damaged from below even when no water touched the top. High humidity or standing water underneath keeps the bottoms of the boards wet, causing cupping. Fixing the floor without fixing the moisture source below means it will cup again. See flooded basement causes and prevention, and fix crawl space humidity before repairing the floor.

To keep wood floors stable over the long run, the NWFA recommends keeping homes between 60 and 80 degrees Fahrenheit and 30 to 50 percent humidity, year-round.

What affects the cost

Cost depends on:

• Floor type: solid hardwood can often be refinished; laminate is replaced
• Area affected and whether boards can be blended with the existing floor
• Subfloor condition: drying versus replacement
• Water source: contaminated water means removal of porous materials
• Drying time and equipment
• Refinishing the whole room so color and sheen match

Fixr's water damage restoration guide (updated January 2025) lists subfloor repair at $250 to $750 for a 150-square-foot section. Those are Fixr's national figures; flooring replacement or refinishing is priced separately. See our water damage restoration cost guide for the bigger picture.

Insurance

A floor damaged by a sudden leak, like a burst supply line, is more likely to be covered than one damaged by slow leaking or high humidity over time. The Insurance Information Institute notes that an HO-3 policy covers accidental discharge of water from a plumbing system, while seepage is treated as a maintenance issue, and flood damage requires a separate flood policy. Check your own policy before tearing out flooring, and photograph everything first.

Getting help

If water got under a large area, the floor is buckling, or you can't tell whether the subfloor is dry, a restoration company can measure moisture under the floor and set up controlled drying, and a flooring contractor can advise on refinishing or replacement. Our water damage restoration guide explains the full process. To find companies near you, browse our locations.

Flood Rescue Pros is a free service that connects homeowners with independent local water damage restoration companies. Get help now.

Frequently asked questions

Is it bad to get hardwood floors wet?

A quick spill wiped up right away is usually harmless on a finished floor. Standing water, wet mopping and leaks that sit for hours are what cause cupping, stains and finish damage.

What pulls moisture out of wood floors?

Steady airflow and dehumidification. The EPA recommends dehumidifiers, gentle heat and fans for wood surfaces, with caution on heat for hardwood floors. Professionals may also use floor drying mats that pull moisture up through the boards.

My wood floor is bubbling up. What could be causing this?

Raised or buckling boards usually mean the wood or the subfloor has absorbed water and swollen. Look for a leak nearby or moisture coming from below, stop it, remove water and dry the floor before deciding on repairs.

Will a wet wood floor go back to normal?

Mildly cupped hardwood often flattens as it dries. Wait until moisture readings are back to normal before sanding, or the floor can end up crowned.

Can laminate floor water damage be fixed?

Swollen laminate planks cannot be repaired, only replaced. If only a few planks are affected and the subfloor is dry, those planks can often be swapped out.

How do I know if my subfloor is damaged?

Soft or spongy spots, a musty smell, mold visible from below, or boards that keep cupping after the surface dries all point to a wet or damaged subfloor.

Key facts

• Wood swells as it gains moisture and shrinks as it dries, which causes cupping, crowning and buckling.
• Remove standing water immediately and dry with fans, dehumidifiers and only gentle heat, per EPA guidance.
• Mild hardwood cupping often flattens as the floor dries; sanding before it is fully dry can cause crowning.
• Swollen laminate does not recover and is replaced; dry, undamaged planks may be reused.
• Plywood subfloors can often be dried and reused; particleboard that stays wet swells and must be replaced.
• Fix moisture from below (basement or crawl space) or the floor will cup again.