Foundation damage poses a serious threat. The cause of most foundation problems is the soil itself.

The main thing is soil. No matter how good a foundation might be or how it was installed, if you have poor soil and the seasons fluctuate as they do in most areas of the country, you are susceptible to sinking and leaking foundations.

Drought, trees and sewer leaks (which causes one area to be most saturated than others) accelerate the process.

Today's newly constructed homes also are being built very quickly in areas where we could not build before. If you are planning on building a home, it is a good idea to have a soil engineer do a survey to find out what the soil conditions are in advance. You never know when you will find too much clay or peat or even an abandoned landfill that will shift and condense over time. These conditions are not good for the stability of a foundation.

Any time you put a rigid material on a flexible earth, it is bound to crack. There are a lot of products that can be used as dampproofing and waterproofing, but unless you build above the water table and have the proper scope on the land, water is going to come through somewhere.

What can homeowners do to stave off foundation problems? It might sound silly, but you need to water your foundation and you can't do it with a sprinkler. To thoroughly water the soil around the foundation, you need to install a soaker hose about 6 inches away from the foundation and bury it a few inches underneath the soil. This would insure that the water will go down into the ground and not evaporate from the surface.

There are many situations in which you can have a foundation problem that doesn't require foundation repair.

With a plumbing leak, you can fix the leak and wait a year before having the house reevaluated. With a plumbing leak which may occur underneath the foundation floor, the soil needs to take time to dry because it can not evaporate from underneath the slab. Often it will fix itself.

When water pools at the foundation perimeter, the soil will swell and pick up the house. Again, fix the drainage problem and wait a year for the house to come down. If every spring the house goes up again, you have water moving under the foundation and will need to put a moisture barrier several feet below the surface.

A French drain will get rid of underground water, surface inlets will remove surface water and a pump will move it all out into the street.

The third problem is trees. If your house is starting to move down in a certain area, and you have trees in your yard that are getting bigger, then the roots are most likely under your slab and drying out the soil underneath. Tree roots extend about 1 ½ - 3 times further that the height of the tree. A tree about 12 inches in diameter and 30 feet tall uses 150 gallons of water a day in the middle of summer.

A root barrier can solve this problem, which consists of digging a trench about one foot deeper than the foundation and applying a certain material that roots can't grow into. Wait about a year and keep your foundation watered and see if it comes back up.

To help you assess the seriousness of your problem and decide if you do need foundation repair, you might want to monitor cracks that appear in your plaster, tile or brick. One good way to do that is to draw a diagonal pencil line across the crack and lightly record the date. You can then see if the crack grows and how quickly.

If you start to notice the floors creaking and the windows and doors are sticking, or if you see water in the basement, then you have had some movement in the foundation and water is the culprit.

Keep soil away from the house (especially clay) and make sure that there is a slope away from the house out into the yard so water is not trapped up against the foundation wall. Look for cracks in the foundation as well as basement walls that are bowed in. This also signifies problem.

To control basement moisture, traditionally the exterior of a home can be excavated, then a tile system teamed with a wall coating can be installed. New technology has introduced products on baseboards and subfloors that help drain water to a sump pump and ultimately away from the home.

For bowed walls, products are available to stop the inward movement. Sometimes all you can do is call a professional. This is a big job that might involve lifting the house and replacing the foundation in extreme situations. It can be very costly and time consuming.

For foundations that experience sinking there are several form of piers being used today.

Drilled Piers involve drilling a series of holes around the foundation down to the level of stable soil and then installing each pier using steel rebar and poured. The concrete requires seven days to set up, so the crew must return later to actually level the foundation. The jack up the house above each pier and stack pre-cast concrete blocks and steel shims between the pier and foundation until the foundation is level all around. With this method the weight is transferred from the house to the bottom of the pier.

Piles are more recent methods developed in the 1970's. They are underground support systems made up of a series of cylinders that measure six inches by 12 inches.

With concrete piles, the cylinders are hydraulically driven into the ground one on top of the other until they won't go any further. The foundation is leveled as soon as all piles have been driven. One type of concrete pile uses solid cylinders that are simply stacked vertically underground. The other types use cylinders that have hole in their centers. Either cable or rebar is run through the holes, thereby improving lateral support and alignment.

With steel piles, sections of pipe are pushed into the ground with the same method. The steel pipe is narrower, about 3 inches in diameter, than concrete, which is about 6 inches. This means it take less force to push the pipe into the ground and it also goes deeper than concrete.

On both of these methods, the weight of the house is transferred from the surface to the sides of the piles. It holds the weight of the structure because the soil grabs hold of the pier. This means it has a lot more longevity than drilled piers. This is why the warranties are longer.