Causes of Foundation Problems
The need for foundation repairs arises from a combination of heavy rains, hot drying summers, occasional plumbing problems, highly expansive soil of the Houston area and poor foundation design.
A foundation fails either because it is unevenly lifted by expansive soil, or the soil fails to provide adequate support.
Steel piers and helical steel piers provide excellent long-term support for house leveling.
Causes of problems include:
Clay soil expansion and contraction
Sun and drying heat
Trees and shrubs
Poor clay soil compaction
Retainer wall failure
Inadequate foundation building codes
Houston's soil is most often the root cause of our foundation problems. Our soil contains varying levels of a clay material called Montmorillonite. Due to the presence of this clay, water may cause the soil to expand by as much as 30%, up to 6 or more inches in some areas of Houston and surrounding cities.
Different levels of moisture around the perimeter and under the house create upheaval, slumping and slab breaking forces.
It is also possible that the foundation problems began during construction, due to inadequate soil compaction, improper land slope (drainage), or inadequate foundation design.
Watering Excessive water on one or more sides of a house causes soil swelling (upheaval at the perimeter, while the center of the foundation remains relatively stable. Stress builds and the slab breaks, leading to the need for foundation repair and house leveling.
When moisture causes foundation upheaval, the cure is drainage correction.
Drainage: When land slopes toward the house, water flow is under and around that portion of the foundation, causing swelling and sometimes soil erosion and foundation slumping. Land slope must be downward, away from house. Check for adequate drainage of A/C units and gutters.
There should be no ponding or pooling of water near the house. Sometimes a neighbor will change the drainage by adding soil or the addition of a retainer wall, causing excessive water accumulation and the need for house leveling.
Sun and Heat: Areas of the foundation that receive full sunlight will dry out first. In summer and winter, walk around the home and look for soil pulling away from the slab.
In the absence of shade trees, the Southwest corner quickly bakes dry each summer, causing the foundation to crack and requiring steel piers or helical piers for foundation repair.
Trees and Shrubs: Planted close to the house, roots reach under the house, sucking moisture, causing excessive drying and soil shrinkage.
Plumbing Leaks: Localized swelling of the soil and uplifting of the foundation occurs due to dripping fresh water or sewage pipes. When left unattended, the moisture will cause the need for foundation repairs.
Soil Compaction: Builders sometimes fail to adequately compact the soil. Poorly compacted areas provide inadequate foundation support, leading to foundation failure.
Retainer Wall Movement: Both wood and concrete brick or rock retainer walls can fail, either by collapsing, or simply moving away from a house. When this happens, soil may drop away from the foundation.
Inadequate Building Codes for Foundation Construction: Texas and specifically the Houston/ surrounding cities residential foundation building codes have traditionally been deficient in preventing the need for foundation repair and house leveling. Los Colinas was one of the first Texas cities to establish a building code to mandate above ground concrete slab on piers. The concrete slab is literally elevated above the ground using piers or pilings installed to bedrock. For older buildings, steel piers, helical piers or concrete pilings should be installed to provide adequate foundation support and repair.