Foundation inspection is the process of inspecting an already-built foundation for faults that would compromise the structural integrity of the structure. Foundation failure may be brought about by the excessive differential settlement of the foundation, changes in the ground conditions, change in the use of the building leading to higher pressures at the foundation level or simply the inability of the ground to carry the weight of the building due to poor design by the engineer.
Inspecting building foundations is occasioned by indicators of foundation failure. It is important to take note of the indicators of foundation failure. Mild foundation failure will influence the serviceability of the building. Furniture will not be stationary, and doors and windows will not lock or open properly. In excessive foundation failure, the buildings structural system will fail, leading to the possible collapse or redundancy of the building. Therefore, Home Design is very critical to ensure that a building is fit for occupation.
Inspecting foundations may vary from conducting a visual inspection of the structure to using specialized equipment to assess for foundation failure. Visual inspection consists of external and internal inspection. One of the main external indicators of foundation failure includes a slanting structure. As a common rule of thumb, the degree of slanting should not exceed 2°. The degree of slanting may not be obvious, and it may require someone with a keen eye. Examples of internal indicators of foundation failure include cracked walls and floors, sloping and uneven floors, and jammed windows and doors. The cracking induced on the building’s elements is as a result of the accumulation of stresses due to excessive differential settlement. Cracks, however, are not a conclusive means of assessing foundation failure during Home Design. Cracks in the buildings elements may be as a result of the curing of concrete or the exposure of untreated timber to the weather elements.
Once the foundation is found to have failed, the foundation inspector recommends repairs as per the findings of the Home Design. Foundation repairs include sealing cracks in the building’s concrete and stone elements, replacing weathered wood and steel elements, and leveling floors. In extreme cases, the foundation of the structure needs to be strengthened to prevent further settlement. The process of strengthening the foundation is referred to as underpinning. Underpinning involves excavating up to the foundation of the building, providing temporary support for the building using props, and increasing the depth or the width of the existing foundation.