If your home is experiencing foundation failure, such as cracks in the foundation or soil separation, then you may need foundation repairs. Finding the right foundation repair specialist can be a difficult process because each company offers different repair methods for fixing your home's foundation. That is why it is important to know the important details of every foundation repair method--including concrete press piles--so you know if you are getting quality products.
There are many different types of foundation repair products available to repair your home. These include steel resistance piers, helical piers, and concrete pressed piles. Unfortunately, they all do not perform well or even meet the building code.
Concrete pressed piles or concrete cylinders do not meet local building codes for several reasons. First of all, they do not meet depth requirements. The depth of the pile or pier or any type of deep foundation system is probably the most important factor for an effective foundation repair system. No matter what foundation repair system is being installed, if this pier is not deep enough, it becomes a useless pier. Unless the pier system is installed below the active zone or zone of influence (as many engineers refer to it) it will not be able to support your home.
Concrete pressed piles are considered a friction pile – one that relies on skin friction with the soil to produce load holding characteristics. When these piers are installed in the active soil zones (typically 15’ or less), the addition or subtraction of soil moisture causes concrete pressed piles to move with the soil. Due to their diameter and the blunt surface, they are very difficult to drive past this active soil zone without doing damage to the home.
Steel piers and helical anchors not only do not rely on skin friction for support but also are designed to penetrate beyond the zone of influence which provides a stable pier to support your home. These piers are designed with the ability to go very deep if necessary, well beyond any moisture fluctuations in the soil. Steel piers have a much more slender nature which greatly helps their ability to penetrate dense soils, which are present during droughts or extended heat spells. Helical piers are screwed through the soil and use helix shaped flights or mini-footing to support your home's load. When installed beyond the active soil layers helical pier provide a very solid support for your foundation.
Next, concrete press piles do not provide a true connection between cylinders. This not only poses a problem with meeting building code minimum requirements but also creates a major problem for homeowners. As the concrete cylinders (12 inches each) are pressed into the soil they often times become misaligned. Picture a stack of blocks sitting on the floor. Now apply a force to the top block. You will notice that the blocks start to move side to side as more pressure is added. This exercise is consistent with how concrete pressed piers act when a bottle jack is used to force them into a hard soil.
Steel piers and helical anchors use a mechanical connection between the pier sections to maintain alignment and provide consistent support for your foundation. Helical anchors, due to their design, provide an additional benefit in that they equally resist upward and downward movement upon proper installation.
Often, foundation repair contractors that use pressed piles, will place a cable or reinforcing bar down the center of the pile to help compensate for their alignment downfall. This attempt in maintaining alignment is admirable but not effective. As the concrete cylinders move through the soil they will encounter varying soils which cause them to turn or curve. Once this takes place, any large force that is not exactly centered on a concrete cylinder can cause it to crack or break. Once the concrete cylinder has cracked you can expect your foundation to settle at this point.
While all foundation repair methods require proper training and education to provide any long-term solution to your foundation problem, concrete pressed piles, due to their very nature, are prone to the unique issues covered above. Their design causes them to be driven shallow and often times at angles that do not provide long-term support. Even if your city does not require foundation repair methods to meet building codes, as your home is your most valuable asset, you should demand the use of steel piers and helical piers by your foundation repair contractor. Manufacturers like Earth Contact Products design and engineer their systems to provide long-term support as well as educate their network of foundation repair experts in the science of foundation repair.