Single Press Concrete Pier
Use of pressed concrete piers is the most popular method of foundation repair and probably accounts for more home foundation repair installations than all other methods combined. It is effective in most scenarios and is the only solution in areas where there is no bedrock or soil dense enough for other methods. It also usually costs less than other repair methods.
- It is quick, usually 1 to 4 days depending on the number of piers
- If installed correctly, it is extremely reliable
- It is installed directly beneath the foundation
- It is very cost-effective
- Installation can be messy because a large amount of soil must be removed in order to provide a working room beneath the foundation. Most contractors provide sheets of plywood or other materials to hold the soil until it needs to be replaced. Any excess can be used in low areas or hauled away.
- Plants may need to be removed, but most companies will carefully remove them and replace them upon completion.
With Rebar Reinforcement
Many concrete piers are manufactured with a 5/8 inch hole running the length of the pier so that it can be threaded on re-bar, cable, or other material that is rigid enough to prevent lateral shifting. In areas where there is no lateral shifting solid concrete segments work just as well with the added benefit of being stronger.
HOW IT WORKS
- Holes are dug at intervals along the affected areas of the foundation. If a pier is necessary in an area that is covered by concrete then a hole must be cut through the concrete.
- After the holes are dug, a hydraulic press is used to force the concrete segments into previous using the entire weight of the foundation to force the lower segments deeper.
- This process continues until the piers reach bedrock or until the friction between the soil and the surface of the concrete segments becomes so great that the weight of the foundation is no longer sufficient to press them deeper. This is commonly referred to as the “Point of Absolute Refusal.”
- After all piers are pressed to the point of absolute refusal, hydraulic jacks are used to raise the foundation in multiple locations and a concrete cap and steel shims are placed between the top of the pier and the foundation. The jacks are then slowly released allowing the weight of the foundation to rest on multiple piers at the same time, insuring that the weight that each pier supports is only a fraction of the weight that was used to press it into place.