Foundation is one of the most vital elements of a structure as its safety and performance affect the entire building. Any kind of negligence during the construction of foundations would mean compromising the safety and serviceability of the building.
Therefore, it becomes important to understand the indications that point towards foundation issues so that a construction inspector can diagnose the problems quickly and present suitable preventive and repair measures.
Signs of foundation problems may include cracks in walls, floors, and foundations, settlement of the building, foundation upheaval, sticky doors, etc.
- What are the Indications of Problems in Foundation of Residential Buildings?
What are the Indications of Problems in Foundation of Residential Buildings?
1. Cracks in Foundation, Walls, and Floors
If cracks are observed in the foundation, floors, and walls, it signifies foundation issues. It may be argued that hairline cracks, in the first three years after construction, are normal. Nonetheless, horizontal cracks in the basement walls are signs of trouble and are usually caused by unacceptable foundation settlements.
Horizontal cracks are considered to be more severe than vertical cracks. This is because horizontal cracks show that the perimeter of the property foundation is subjected to tremendous pressure.
The width of serious cracks is generally greater than 15 mm. If the cracks in the interior walls are positioned at 45 degrees, they indicate a considerable foundation movement. Such great movements will create large tears in the wall over time.
Cracks near the openings of doors and windows are the signs of quick foundation settlement. Stair step crack patterns in brick walls are also signs of foundation trouble.
2. Foundation Upheaval
The upheaval of a foundation is the upward movement due to the expansion and contraction of the soil underneath the foundation structure. Clay soil is commonly expected to cause upheaval as its volume increases when it becomes wet.
Generally, the perimeter of the foundation slab is affected by heaving, but other parts of the building, like doorways, and hallways are not entirely protected.
Frost heave is another cause of foundation issues as it leads to foundation movement. Frost heave occurs when moisture in soil freezes; its size increases by 9%, which consequently exerts pressure on the foundation.
3. Foundation Settlement
Settlement of the foundation is a sign of a problem, especially when one side of the building is lower than the other or the center of the building is sinking. Generally foundation settlement creates vertical gaps.
Differential settlement is the worst case of building settlement, leading to significant structural modification. It initiates extensive vertical cracking on the inside and outside of the building wall. Differential settlement may be caused by an uneven distribution of loads on the foundation, variation of moisture content of underlying soil, variation of soil properties underneath the foundation, etc.
If you notice a single vertical crack in a foundation, it could be a sign of upward movement of the foundation structure. A sudden settlement of a part of a building may indicate the presence of a sinkhole under the foundation.
4. Uneven Floors
If a concrete floor seems to be uneven or out of level, it can be a sign of a foundation problem. Foundation movement drives the floor out of level, and the problem cannot be solved unless the movement is stopped.
5. Doors Do Not Open Properly
If doors in a building do not open and close smoothly, it signifies a problem with the foundation. This is commonly caused by foundation settlement that drags down doors and causes them to jam slightly, making opening and closing of doors difficult. The sticky doors may be accompanied by crack development in the foundation. This is a sign of foundation settlement.
However, sticky doors due to foundation issues should not be confused with the ones due to humidity. The latter occurs approximately after two days of continuous rain.
Sometimes, extreme heat dries the soil underneath the foundation and causes soil movement. This may be the cause for the door not opening and closing properly.
6. Gaps Around Exterior Doors and Windows
Gaps around the frames of exterior doors and windows indicate foundation issues. When such problems occur, it is recommended to carry out a visual inspection of the foundation to check for cracks.
7. Separation of Counters and Cabinets from the Wall
If a gap between counters or cabinets and the wall of a building is observed, it could be a sign of foundation trouble. A gap of 1.27 cm or more indicates the occurrence of a major problem.
Signs of foundation problems may include cracks in walls, floors, foundation, settlement of the building, foundation upheaval, sticky doors, uneven floors, separation of counters and cabinets from the wall, and gaps around exterior doors and windows.
If the problem of a foundation is not tackled, it would indeed exacerbate, and as time goes by, both the cost and efforts required to fix the problem will increase.
If cracks on the wall are long and horizontal, then it is considered dangerous and severe settlement could be the underlying cause. When the foundation wall is built from a concrete block, the cracks develop like stair steps.