Why Foundations Settle

cracking brick wall

A settling foundation in the greater St. Louis and St. Charles Missouri area is often the first step to serious home damage, including wall cracks, tilting chimneys, sticking doors and windows, and, most importantly, the potential complete failure of the foundation itself. Foundation settlement is a common problem in Missouri and will only become worse (and more expensive to repair) over time, it’s always in your best interest to begin settling foundation repairs sooner, rather than later.

Foundation settlement will continually compromise a structure. Eventually if it’s not repaired or replaced, the foundation will fail completely, with potentially disastrous results. Foundation replacement is the most invasive, expensive, time-consuming, and disruptive solution, but if the foundation has deteriorated to a very advanced stage, it can be the only way to address the problem.

The foundation and its footings are dependent upon the soil that surrounds it to hold the foundation in place. On paper, this design should stand the test of time; however, the one variable that cannot be controlled is that the soil beneath and around the foundation is constantly changing. Unfortunately, soil conditions are rarely considered during the construction of the foundation in residential homes, it’s typically a one size fits all approach in regards to foundation design and often times this approach leads to settling foundation repairs down the road. There are a variety of reasons why these foundations settle.

Expansion and Contraction of the Soil

settling foundation illustration

Many clay-rich soils in Missouri can be defined as “elastic” in nature. In other words, they expand and contract with moisture content. As soils become saturated with water, the clay expands and loses strength. This condition allows the foundation to sink much the same as if you were to place a concrete block on wet mud. Many times repairs are made by simply enlarging the concrete footing by excavating holes beneath it and pouring more concrete to increase its size; this repair method is essentially just placing a larger block in the mud, it’s not the size of the footing that’s causing the foundation settlement, but the soil it’s bearing on. Conversely, clay soils contract when moisture is taken away. Unfortunately the soils do not always lose moisture evenly, which allows one area to contract faster than another. The soils contract, the foundation loses needed support and therefore settles.

Over time, the expansion and contraction of the soils beneath your home will lead to foundation damage. Cracks, sticking doors and windows, and other signs of foundation settlement will begin to show up throughout your home.

Poor Drainage

Improper drainage can cause soil instability by creating localized areas of saturated soils, which softens the soils and allows the foundation to settle. Poor drainage can be due to the localized topography of the area, “French” drains that have become clogged with roots and soil, gutter down spouts, etc.

Poor Compaction

Many homes are built on back-filled soils, which is a common and accepted building practice. However, care must be taken to properly compact the back fill before construction of the foundation. Improperly compacted back fill will slowly consolidate, sometimes over a period of years, which will allow foundation settlement.

Plumbing Leaks

Another potential reason for your foundation problem may be due plumbing leaks that allow water to saturate or erode the soil under or around your home. The water created from this problem is constant and will only continue to deteriorate the soil conditions around your home’s foundation.

Tree Roots

Many varieties of trees and large shrubs consume vast quantities of water. For example, some experts report that one large pine tree can remove as much as 30 gallons of water from the soil daily. If trees and large shrubs are located in close proximity to the foundation, excessive moisture loss can result. This will allow the soil to contract and the foundation to settle.

The Good News

Although a settling foundation problem is very serious, Missouri Basement has permanent, engineered solutions available to correct your problem. Contact us today to schedule your free foundation inspection.

Missouri Basement BBB Business Review