What should I know about foundation repairs?

There are not only different kinds of foundations, there are different kinds of repairs.

Effects of the ground on a foundation can cause stress and failure to a home's foundation. Precautions for a healthy foundation are essential if you want to prevent expensive repairs. There really isn't that much you need to do maintain a healthy foundation.  

The design of the foundation, will determine which repairs methods work best. Slab foundations are typically repaired using concrete press piling, steel press piling, steel helical piers or bell-bottom piers. Crawl space foundations are typically repairs by simply replacing old or damaged piers or by simply re-leveling the house.  Basement foundations suffer mostly from water penetration so most repairs for this type of foundation are related to stopping the water from getting in.

The most common repairs in the southern states are for slab foundations and pier and beam foundations.  Here are some of the most common repairs:

1. A bell-bottom pier is where you actually drill a hole in the ground, create a bell at the bottom for the bearing component of the pier, then pour concrete down into the hole. This pier is then uses to lift and support the house’s foundation. 
2. Some foundation repair contractors claim that the steel pier method is considered the best in long run. The advantage of using a narrower, steel pier is that they can be pushed through the stiffer soils better than the concrete piling. The harder and more stable steel pier can be driven into solid rock or a hard loading bearing material at much higher pressures of up to 10,000 PSI. Steel piers can also be driven to depths of as much as 60 feet. A foundation repair using steel piers typically takes one to three days to complete. Steel helical piers are also an alternative to digging a hole or pressing a piling. Steel helical piers are drilled into the soil using a machine that measures the pressure the tip of the dill is exerting on the ground. When a pressure increase is measured that indicates a proper load bearing soil, the drill ceases and the pier is cut to fit under the house.
3. Some in the industry considers the pressed piling method of repair a fast, easy and clean solution. The pre-cast piling is mated with a solid core of steel and concrete then hydraulically driven using an installation force of 5000 PSI. Because of certain to soil characteristics, mechanics of friction and compression, this system can attain support strength of twice its installation force within one month after installation. 
4. A more economical repair method is to drill or pour concrete piers. Holes are typically drilled to a depth of 9-12 feet below the ground surface, and then filled with reinforcing steel and concrete. Poured concrete is topped with concrete spacers and shims and the house is supported on this structure.

Any foundation repair work should begin with hiring a structural engineer’s evaluation of the site or structure. They will be one to test and determine which foundation system or repair would the best for your situation. Having a structural engineer involved is essential. Without their involvement, you chances of future problems is increased. The engineers job is to design and ensure the proper implementation of the design into the repairs. You should also consider a hydrostatic test especially if there is substantial deflection (greater than 2’ deflection over a 20’ span) or cast iron drains under the slab.

Regardless of they type of house you have, there are some necessary tasks you will have to do stay on top of things.  Learn more and keep up with your house with a free My Healthy House.com profile.  Stay tuned and make your house the best it can be.  

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