Five Possible Causes for Sunken Driveways
There are many reasons you might experience a sunken driveway. Driveways are typically designed to last for years, usually 25-50 with proper installation but only if properly installed. Proper slopes, usually one-fourth an inch per square foot, should be installed to discourage water drainage to keep water from resting on your driveway. When driveways happen, the first thing is to do is to determine the cause so it can be fixed. Otherwise the problem could keep occurring.
The first thing that happens before a sunken driveway occurs is cracks in your driveway. Cracks are the first sign of weakness in your driveway before you notice spots and holes. These spots and holes eventually lead to sunken driveways.
Extreme temperature conditions are another reason you experience sunken driveways. One heavy downpour is not likely to cause cracks and sinks in your driveway, but a decade or more of extreme rain, ice and snow can cause weak spots, cracks and sinks in your driveway.
Animals and rodents could be the cause of sunken driveways. Animals and rodents, which dwell in the ground create homes in the ground. Sometimes these vast tunnels are located under the driveway. These tunnels then create large pockets of air under the driveway. Once vehicles drive over these air pockets, the driveway is not able to withstand the weight. The result is cracks, holes and sinks in concrete driveways.
Tree roots grow and grow. Large trees have enormous roots, which span many feet under the ground. These roots can burrow their way underground including under the ground of your driveway. The tree root must move the dirt in order to grow and this means your driveway could actually lift up to make room for the tree roots. The area that lifts up will eventually separate from the other areas causing sunken driveways.
The base that your driveway is built on is just as important as the driveway itself. Not building driveways on the proper soil can cause them to sink into the ground. Clay soil and soils, which erode easily, will either expand or shrink over a period of time during inclement weather. This causes the driveway to either rise or sink. When this motion happens, it causes spots that are not level leading to cracks and sinks.
The average width of a one-car driveway is eight to nine feet, and for a two care driveway is 15 to 18 feet. This is a lot of concrete to repair due to problems. Properly addressing the causes of problems alleviates them so that repairs can be a onetime deal, rather an a yearly or semi-yearly ordeal.