Concrete piers are columns of concrete formed when wet concrete is poured into holes that have been dug into the ground. They can also be referred to us supplemental support devices or systems placed under house foundations to lift or stabilize the house.
What Underlies The Use Of Piers?
The principle behind foundation repairs with concrete piers is to extend the depth of the foundation so that it is supported by a more stable soil layer, and extend its breath so that its load is distributed across a wider area.
Need For Concrete Piers
The need for piers for foundation repair arises out of either changing structural conditions of the soil that supports the foundation or emerging factors that makes a house that was once stable require further support. How?
The foundation of your house is laid on a soil layer. Naturally when this soil soaks in water either through rains or moisture from underground, it expands. When it is dry, it shrinks. This expansion and contraction eventually results in soil movement or subsidence. You will notice this movement by seeing cracks in your slab. Cracks are an indication that somewhere on the house, the ground has moved. Other tale tell signs include having doors and windows that won’t shut properly or tilting of the house.
Other reason for foundation repair could be that the user needs of the house owners have changed therefore the house requires a more robust foundation. Natural hazards like floods and earthquakes can also affect the stability of the house. New constructions adjacent to the house may have caused soils supporting the present foundation to be excavated resulting in an unstable house. It may also be necessitated by a cost-benefit analysis that shows that it is cheaper to repair the existing foundation than to build a new one.
How Are Piers Installed?
Installation of concrete piers is a fivefold process. First the location or points along the foundation where piers need to be installed are identified. A hole measuring 12 inches in diameter is then drilled to a depth of al least 12 feet below the foundation. Then reinforced steel bars are joined together and placed into the hole. The piers are then let to cure for a week in order for the concrete to harden.
When all the piers are dry enough, hydraulic jacks are brought in and placed on the pies. They are then used to lift the foundation. After the foundation is lifted, spacers made of concrete and steel are placed on the piers to offer support for the foundation. The hydraulic jacks are then removed. Lastly the piers are covered and the voids left after piers have been mounted filled.
The advantage of this system for foundation repair is that piers can be designed to bear any load, are simple to install, are relatively cheap when compared to other foundation repair methods, last long and the warranty is transferable to a new owner.