Foundation wall anchors are slightly more effective solutions for bowing foundation walls. Helical anchors consist of a long rod with a corkscrew end that attaches to a wall plate inside of the foundation wall. To install these, large holes are created in the wall (or in the case of block walls, blocks are removed) where the anchors will be installed. A helical anchor is drilled through this hole into the soil. The hole is refilled with concrete, and the wall plates are installed.
The weaknesses to these systems are important to remember. The large holes in the block weaken the structure, and when they're filled in, it's very difficult to make them watertight, which can lead to flooding later. The soil that these anchors are bracing against is disturbed by the corkscrew's drilling into it. Heavy equipment must be used during the installation, and the process tends to be very expensive. It's certainly better than steel beam reinforcement, but this is still not the best option.
Wall anchors are designed with three main parts: an exterior earth anchor, an interior wall plate, and a connecting steel rod that. Together, they work to counteract the pressure being exerted against the wall.
When foundation anchors are installed, a small area of lawn is removed, and the space underneath is excavated. The earth anchor is placed inside the hole, and small is drilled through the foundation wall from the inside. A steel rod is driven through this hole and is pushed out to the earth anchor in the yard. On the outside, an anchor is fixed on the rod, with a wall plate installed against the inside foundation wall. This anchor is tightened against the wall, and the tightening process is repeated over time. Once the installation is finished, the hole is filled in, and the removed portion of lawn is restored.
Over time, periodic retightening of this anchor can potentially pull the wall back to its original position- a possibility that merely providing a brace cannot present. Foundation anchors are a cost-effective and fast installation, usually installing in a single day. Installation is possible year-round, and the job is completed with minimal disruption of the yard and with no need to replace the foundation.
However, Foundation Anchors are useful only in application against bowing, bending walls. If foundation settlement is your issue, then you may wish to consider foundation piering instead. Click to read about foundation piers.