If you’re in the process of buying a home or already living in a home in which you’re noticing more and more cracks, jammed doors and windows, sloping floors or nail heads protruding from the walls, making that call to a foundation repair specialist can be scary. But the more educated you are about foundations, the better equipped you will be at selecting the right contractor and finding the best repair solution for your home.
The American Society of Civil Engineers estimates that one quarter of all homes in the United States have some damage caused by expansive soils. In a typical year in the United States they cause a greater financial loss to property owners than earthquakes, floods, hurricanes and tornadoes combined.
Why do we have so many foundation issues in Texas? The Texas State Historical Association’s division of land resources recognizes over 1,300 different types of soil in our state, each with its own distinct attributes and characteristics. The combination of variable seasonal weather cycles and expansive clay soils stirs up the perfect storm for foundation issues, and Dallas properties have their fair share of them. Damage is caused when fluctuation in the soil’s moisture content causes it to expand and contract. Constant heaving and shrinking of the soil underneath the slab can break the foundation of a home, causing it to sink.
Even in light of Texas’ soil problems, slab foundations are usually still considered a better alternative to pier and beam foundations, which cost more and require added time and expertise to build; they have their own set of problems including the exposed crawlspace that has to be properly sealed to prevent moisture infiltration leading to mold and rot, rodent and insect infestation, and freezing of water utilities.
State building codes provide general guidelines, minimum footing requirements and presumptive soil-bearing values for various soil types, bearing capacities, material requirements and estimated lateral loads. But a building code cannot accurately predict your building project’s specific needs. Even in the same neighborhood or right next door, the soil on one home site can differ from the next.
In order to obtain a third-party insurance-backed structural warranty on newly built homes, a structural engineer’s stamp of approval on the foundation plan is required. It is important that your engineer is familiar with our area’s specific weather conditions and soil types. Structural engineers start with a soil analysis and use science and math based information to understand various relationships between soils, hydrostatic pressure, water flow, and other factors which affect foundation walls’ long-term structural strength.
Steel reinforced slab foundations are generally the cheapest and are fine when building on stone or rock. Slab on grade beam uses a concreate grade beam with traditional rebar. Slabs with piers and grade beams are best, but also more costly.
Even the best laid plans cannot guarantee a home against foundation issues. Tree roots that suck up water in the soil and plumbing leaks are some of the common issues that can cause foundation problems. Repair recommendations to a slab foundation may include slabjacking, which involves pumping grout mixture into the space beneath the concrete as a way to float it back to its initial position, or piering, which involves digging eight to 15 feet into the ground to set up pressed concrete or steel pier supports that can hold the weight of the foundation and level it to prevent further damage.
A qualified home earning a new home warranty will cover structural defects for 10 years and be transferrable to the new owner until its expiration date. It is important to note that foundation repair warranties for work done on homes after the 10 year new home structural warranty period are specific only to the areas of the house that were serviced.