Many properties across the UK were built using traditional methods over the centuries, often designed with solid walls consisting of solid brick or stone, with in-built structural timber. Over the years these properties are subject to vibrations, subsidence, water damage and many other factors, especially in buildings with shallow foundations. This can cause cracks in the masonry to form, and increase in size over time.
It was not until the 1920’s when buildings were consistently built using cavity walls, that the two leaves of brickwork were connected using metal wall ties. Due to quality issues these can often corrode and cause issues and ultimately break, meaning they need to be replaced.
This is a particularly common problem in properties along the coast, as salty sea air can increase the corrosion of the wall ties, especially once cracks form and moisture can enter the mortar.
Some of the most common causes of structural damage in properties are:
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Subsidence and ground movement - Movement and subsidence from unstable ground can often lead to cracks in walls. This can be further increased in properties with shallow or no foundations.
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Poor drainage and water damage -
When drains and guttering become blocked or damaged it can lead to ground movement due to waterlogged soil. Penetrating damp from wind driven rain can also penetrate into cavity walls and corrode wall ties.
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Defective building materials - Porous or erosive building materials can lead to structural problems. Newer properties built using metal wall ties are susceptible to corrosion. In older and historic buildings built of stone and rubble, water ingress can lead to instability, causing bulging and bowing of walls.
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Removal of loadbearing frames - Buildings that have removed the original timber or steel windows are susceptible to lintel problems, as the original frames were often loadbearing. This is often the case when they are replaced with uPVC windows that are not capable of holding the same load, putting more pressure on the lintel and brickwork above. In some properties the lintel is missing and this can cause cracking or collapse when the old window is removed.
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Timber decay and timber infestations -
When structural timber becomes saturated it can cause woodworm or fungal decay problems, ultimately losing its ability to support heavy loads. This can cause the brickwork above to move, causing cracks and failure.
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Lack of maintenance - When gutters and drains become blocked or defective, moisture can penetrate into the fabric of the building, affecting wall ties and structural timber. It can also cause mortar to deteriorate and the spalling of brickwork.
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Environmental factors - Environmental factors such as trees with large root systems extracting moisture or causing ground heave can cause structural problems for properties. Buildings built close to busy roads may also be affected by large amounts of traffic passing by, which causes vibrations in the property.
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Poor Workmanship - A common reason for structural problems is ineffective DIY fixes that do not address the root cause of the issue. Sometimes properties are built using incorrect products and materials, which can also cause problems.