If you have hardwood floors in your home, chances are you may have had to deal with water damage or perhaps you will in the future. Water damage can range from very minor - where you may not see the signs of it at all - to very serious, like when the floor is flooded with water from a broken pipe or an ice-maker hose.
Very often, the extent of the damage is determined by how long the water is on the floor before it is discovered and dealt with. Sometimes the water travels underneath the hardwood and is not at all visible from above. It becomes visible when warped boards begin to appear.
Cupping: In the picture above, you see an example of cupping caused by water or excessive moisture on the bottom side of the floor. The moisture causes the underside of the boards to swell. The swelling causes the edges of the boards to push upward which leaves a valley in the center of the boards. This is the most common type of water damage.
Crowning: In this picture, you see that instead of a valley in the center of the baords, the center is raised above the sides. This is caused by moisture that is introduced on the topside of the boards. In the case of a broken pipe or any other situation where water is pouring directly on the topside, the water will filter down to the bottomside and cause cupping. If moisture is introduced more slowly to the topside, it won't filter through and the result will be crowning. One of the most common causes of crowning is when the floor has been cleaned with a mop that hasn't been wrung out adequately. Over time, tiny water droplets can be absorbed into the finish and the top layer of the floor. It may take months or years but eventually the boards will begin to warp and eventually the warping will be visible.
Another common cause of crowning is when the floor is sanded before the moisture in the boards has been stableized. When resanding a floor that has had water damage resulting in cupping, it is important to make sure that the floor has dried completely and is properly acclimated. Otherwise, after the sanding, the underside of the boards will continue to dry, shrinking the wood, which causes the edges to move downward and the middle to rise.
How to deal with water damage: Fortunately, there are solutions for water damaged floors. 90% of the time, the damage can be sanded out, and once again, you will have a brand new hardwood floor. I say brand new because the damage has been sanded away and what is left is a new layer. If the damage has been extreme and the floor has been thoroghly soaked for days or weeks, the floor, or at least a portion of it, may need to be replaced.
These repairs will not be cheap but most homeowners' insurance will cover the costs beyond the deductible. Often times, they will pay to have all connecting hardwood floors refinished even when the damage is isolated to one area. It is very difficult to refinish part of a floor and have it blend in with the rest of the floor.