Reasons for Warped Floors

Types

• It is normal for hardwood floors to expand and contract during periods of high humidity. Small gaps between the planks are normal. Buckling and cupping are two types of very common warping in hardwood flooring. Buckling occurs when the wood comes away from the subfloor. A cupped floor looks more like a washboard where the wood plank rises on the edges and sinks in the center. Sagging wood floors, or warped floors, are the type that slope down in the middle. Sagging is the most serious of the types of wood floor warping. It occurs when there is water under the floor.

Causes

• Moisture is the most common cause of warping. Water is absorbed through the thickness of the wood, causing it to bend or sag. Humidity will cause the planks to expand and shrink. Some humidity is good, since dry air will cause the wood to crack. Too much humidity will cause the boards to warp. Another cause is when water is left on the wood floor, which leads to warping. Too much water used when mopping or a spill left too long will absorb into the wood and cause warping. A leak under the sink, in the dishwasher or in an ice maker are notorious for causing warping in wooden kitchen floors. Moisture getting on the subfloor, a wet basement or a damp crawlspace can leave wood floors sagging or buckling. Water draining toward the house instead of away in the landscaping can leak into the home and cause wood floors to warp.

Prevention

• The best prevention is to keep the moisture under control in your home. This can be done by using a humidifier or a dehumidifier, depending on which type of moisture issue you're facing. Humidifiers can help keep wood floors from drying out in dry months by adding much-needed moisture. A dehumidifier removes any excess moisture caused by high humidity, leaks or spills. Cleaning floors with a vacuum instead of wet-mopping will also help to prevent warping.

Cure

• Fix any leaks as quickly as possible to prevent sagging. Use humidifiers or dehumidifiers to keep the moisture at an optimum content. Fans set up around a wet area will speed up the drying process. Regrade any landscaping so soil slopes away from the foundation. Contact professionals to repair any buckling or cupping. The wood floor and the subfloor will need to be reattached or sanded flat and refinished. A quality finish on the floor will prevent moisture from absorbing into the wood from spills.