Foundation damage poses a serious threat. The cause of most foundation problems is the soil itself.
No matter how good a foundation might be or how it was installed, if you have poor soil and the seasons fluctuate like they do in many regions, you are susceptible to sinking and leaking.
Drought, trees and sewer leaks (which causes one area to be more saturated than others) accelerate the process.
Today's newly constructed homes also are being built very quickly in areas where we couldn't build before. If you are going to build it is a good idea to have a Geo-tech or soil engineer do a survey to find out what the soil conditions are in advance. You never know when you'll find too much clay or peat or your might find that you're looking at building over an abandoned lanDfill that will shift and condense. These conditions are not good.
Any time you put a rigid material on the flexible earth, it is bound to crack. There are a lot of products you can use like 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 the foundation 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 thoroughly with a sprinkler. The best way is by installing soaker hoses about 6 inches away from the foundation, and burying them a few inches underneath the soil. This insures that the water will go down into the ground and not evaporate from the surface.
The are some situations, although you may have a foundation leak, that you do not require a foundation repair:
With a plumbing leak, you can fix the leak and wait about a year before having the house re-evaluated. The soil needs to take time to dry because it can not evaporate from underneath the slab. Often it will fix itself.
Another problem is bad drainage. 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 settle back down.
Grading is important. Make sure there is a slope away from the house out into the existing yard, so standing water is not trapped against the foundation wall.
If every spring the house goes up again, you have water moving under the surface of the foundation and you need to put in moisture barrier several feet below the surface. A french drain will get rid of the underground water, surface inlets will remove surface water and a pump will move it out to the street. Note: This may be something better handle by a professional, but many do-it-yourselfers can tackle.
The third problem is trees. If your house is starting to move down in a certain area, and you have trees in you yard that are getting bigger, then the roots are most likely under yours slab and drying out the soil underneath. Tree roots extend about 1.5 to 3 times further than the height of a tree. A tree that is 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 your foundation and applying a certain material that roots can't grow through. Note: Again this is something possibly better handled by a landscaping company. Wait about a year, keep your soil watered and see if it comes back up.
Many Foundation Repair Solutions
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 diagnal pencil line across the crack and record the date. You can then see if the crack grows and how quickly.
If you are starting 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. Watch for cracking and basement walls that are bowed in. This also signifies problems.
To control basement leakage, traditionally the exterior of a home can be excavated, then a tile system along with a wall coating can be installed. New technology has introduced products on baseboards and into subfloors that help drain water to a sump pump and ultimately away from the home.
For bowed walls, products are available to stop inward movement. In some instances, if too much deterioration has occured, this may involve lifting the house up and replacing the foundation. It can be very expensive and time consuming.
For settlement instances, piers would need to be installed. One form of piers involve drilling a series of holes around the foundation (usually on the interior) down to the level of stable soil and then installing each pier using steel rebar and poured concrete. The concrete requires seven days to set up, so the crew must return later to actually level the foundation. They jack up the house above each pier and stack pre-cast concrete blocks and steel shims between the pier and the foundation until the foundation is level all around.
With this method the weight is transferred from the house to the bottom of the pier. Some piers employ an under-reamed bell shaped bottom section for additional stability called bell-bottom piers.
Concrete Piles are one of the 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 drive. One type of concrete pile uses solid cylinders that are simply stacked vertically underground. The other types use cylinders that have holes in their centers and are connected by either a cable or rebar, thereby improving lateral support and alignment.
The latest method is steel pilings which are sections of pipe that are pushed into the ground hydraulically. The steel pipe is narrower, about 3 inches in diameter, than concrete, which is about 6 inches. This means it takes less force to push the pipe into the ground and it also goes deeper than the concrete method.
On both 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, which is why the warranties are longer.
Choosing a Contractor
Whichever method you choose, be careful. Prices that you are quoted could vary widely and it is easy for homeowners to end up paying for repairs they do not need. Bids for leveling a 2,200 square foot house could range from $8,000 to $20,000 or even more. Most repair companies will do an evaluation for free, but if you are getting wildly different quotes from several companies, it might be a very good idea to hire an objective third party, like an engineer which usually costs about $350-$650. Homeowners insurance used to cover foundation repairs, but now about 89 percent do not.
Perhaps no major repair is as dismaying and expensive as foundation repairs. However, by exercising caution, you can give your house the lift it needs and protect the value of what for most of us is our biggest investment.