Underpinning, Piles & Piers

The most effective way to help reverse the signs of a sinking foundation is to utilize a process called “underpinning”, “piering”, or even “piling”. There are many piering methods available by foundation contractors, but the only true and effective solutions are those that transfer the weight of your home to more stable soil than the soil it is currently resting on.

Helical Piers

Helical Piers contain Helices, or helical flights, that serve as end bearing plates for the weight of the home. These flights are welded to a central steel shaft. The helical shaft essentially acts as a screw that is rotated into the soil.

When using Helical Piers, the helices provide a large amount of surface area to resist or bear the weight of your home. Helical Piles are very effective in deeper soils where reaching bedrock is not possible. The helical flights will produce a force that translates into how much weight the entire Pile or Pier can carry.

Why MDTI Helical Piers?

MDTI supplies the AB Chance Helical Piering System for underpinning applications.

Chance Underpinning & Helical Pier Anchor systems are used to transfer load weight to bearing plates located in stable soil. This patented system brings an economical solution to underpinning systems. Fast, predictable, and measurable are just three advantages of this building code evaluated and accepted system.


Chance Civil Construction is the international leader in earth anchoring and piering. Chance Helical are used worldwide to secure residential and commercial buildings, tower foundations, heavy equipment foundations and many other deep foundation applications.

The Chance anchoring system can be used in areas of residential construction or repair, industrial and commercial applications in limited access areas, environmentally sensitive areas, vibration-free construction, and loads subject to compression, as well as uplift.

AB Chance Advantage

Chance manufactured anchors are rated up to 100,000 pounds each. These are available in round or square shafts, manufactured from high-strength galvanized steel. Special patented brackets are used to stabilize or lift foundations in distress. Chance is the only company with a pre-engineered and manufactured underpinning system evaluated and listed by all the national building code agencies.The success of the Helical screw anchor system is based on decades of similar use of Chance anchors by electrical utilities. With over 100 years of structural engineering experience, the Chance Helical Underpinning System is unmatched. All system components are hot-dip galvanized to increase product life in aggressive soils, and are made in the United States.

Helical Pier Installation

Upon receipt of the plan of repair from a qualified design group or individual, the certified installer proceeds with the repair. One of the best investments you can make is to get a soil boring on your property. This will enable the designer to determine what type of anchor and to what depth it must go to reach stable soil.

The installer will usually excavate a hole at each anchor location wide and deep enough to place a bracket under the foundation. The leading section of the anchor with the proper number and size of helices is installed by a rotary installing machine. Extensions are added until the the proper depth is reached and the predetermined torque is achieved. At the point in which the bracket is added, the load is transferred to the anchor, stabilizing the building and allowing for lift, as according to the plan of repair.