Cracking & Movement
Foundation walls, rafters, floor joists, wooden frame structures and other components might develop thin cracks, crevices or get dislocated allowing room for water seepage or pest infestation.
Common Causes of Structural Cracking & Movement
Structural cracking can be caused when forces, either external or internal, act on the building. Chemical changes within the building materials may also be detrimental to the structure. Some of these factors are:
- Unwanted vegetation – Roots of unwanted plants often penetrate into the walls, roof and foundation of the building.
- Uprooting established trees – Firmly rooted trees which had grown for decades, when uprooted, tend to loosen the ground. This adversely affects the moisture level of the soil, which in turn affects the foundation of the building.
- Expansion/contraction of soil – Soil, depending on its composition, often expands and contracts due to alternate retention and loss of moisture.
- Non-reactive soil – Non-reactive soil containing more silt, sand and gravel often fail to bear much load leading to small cracks and dislocations.
- Exposure to sun rays – The northeastern and northwestern corners receive a lot of sunshine from morning to afternoon. These areas dry up to develop cracks.
- Inadequately compacted fill – Building construction on variable foundations or insufficiently compacted fill often times results in differential consolidation.
- Concrete cancer – Concrete cancer or localized corrosion is the outcome of the permeation of salts into the concrete slabs. Rust spots and scaling or breaking of chunks indicate the presence of moisture in salts.
- Dome effect – Dome effects follow hot & wet summers and warm & dry winters. Moisture soaks under a building and plastic soil to expand into a dome shape. Consequently, external walls tend to bulge on top and crack. Internal walls develop cracks and floors bulge to support the rise.
- Saucer effect – Saucer effects follow long dry summers and cold wet winters. External walls rotate and internal walls develop cracks opening at the bottom of the wall. Floors sag inward resembling the structure of a saucer.
Other factors are the size, shape, position and age of the crack. Widening of the crack suggests lack or failure of intrinsic support.
Cracking and movement are looming dangers to a building, often not prominently detectable. Get in touch with us to detect them before they cause major damage. Our building inspectors will draw detailed analysis reports and provide advice on how to repair any issues.