A sinkhole is a depression, or hole, in the earth's surface. It is generally caused by the eroding or dissolving of rock just under the surface of the land. These can appear in many places throughout the world, but in the U.S., sinkhole damage is most common in Florida, Alabama, Texas, Tennessee, Kentucky and Pennsylvania.

One of the first signs that a sinkhole is forming underneath a structure can be the appearance of a crack on the exterior wall of the building. This fissure usually runs diagonally from the bottom center of the wall, and extends to the top of the wall just under the gutters. It is sometimes referred to as a stair step crack because it normally looks like a flight of stairs going up the side of the building. In brick or block homes, separation of the mortar may eventually occur along this line. A crack of this nature is generally a tell-tale sign that there is an undue burden on the home's foundation.

Another common sign of sinkhole damage is a diagonal crack along the interior of the home. These usually appear just above openings, such as doors or windows. They typically run from the ceiling to the top of the door or window frame. This may result in doors and windows that fail to open and close normally. This type of crack usually indicates stress on the building's walls and ceilings.

Walls and floors separating from one another is also a possible sign of sinkhole damage. This could eventually lead to floors that slope or have dips in the center of a room. Homeowners may be able to feel a floor buckling when walked on. When floors and walls begin to separate, the home is no longer safe to inhabit and will likely need major repair work.

The appearance of holes and depressions in a yard is a definite sign of sinkholes forming underground. These may appear suddenly, especially just after a heavy period of rain. They may range in size from only two to three in (5.1 to 7.6 cm) wide to a foot (.3 m) or more in width. These sinkholes are sometimes mistaken for an animal hole, while other times the ground giving way around the opening confirms to the owner that this is indeed a sinkhole.

If a home has noticeable sinkhole damage, the owner should file a sinkhole claim with his insurance company as soon as possible. If the dwelling needs extensive repairs, he should consult with a sinkhole attorney who can advise as to possible compensation from third parties. Sinkhole damage is a problem that must be quickly addressed in order to minimize the repairs to a homeowner's most valuable asset.