What Is Subsidence?

Subsidence is the slow gradual sinking of a section of land or property. Properties move naturally at very minute speeds, as a result, normal movement is not easily noticed and usually caused no harm to a property. Subsidence, however, is a quicker moving of ground in a downward projection. This shift in property position causes negative effects on properties from cracking of wall plaster to loss of structural integrity.

Causes of Subsidence

There are many factors in property subsidence, a large majority of properties that suffer from subsidence are suffering from many different causes. This is due to the fact that these causes by themselves do not harm the property enough to cause this type of event. These causes range from sustained dry weather to tree location to a property and range in severity.

Age Of Construction

The age of the property is a large factor to its vulnerability to subsidence. This is due to the craftsmanship and materials used during its construction. Every decade new materials are utilised or created and used in property construction. Building standards also change every year. These ranges of materials all have different vulnerabilities as well as standards in which they must be used. The construction age of a property will determine the materials and standards used.

An example of this is that properties built before 1965 were constructed with shallow foundations in comparison to modern foundations. A shallow property foundation cannot hold the weight of the property over an extended period of time. This causes a shift in property position alongside a weakened structure, this all could lead to subsidence.


The weather can impact subsidence.  Areas that get consistent dry weather and areas that are having a long dry spell are more susceptible. This is because dry climates cause the soil to contract by lowering the amount of moisture available. With soil contracting, the pressure on the foundation as well as the location of the foundation can shift. This shift no matter how large or small should not occur so if this occurs under a property it has the potential to significantly impact the properties foundation.

Tree Damage

When looking for properties many people do not look at the proximity of trees and if they do they see it only as a decoration piece. Trees on a property can increase the value as well as the look of a property. However, the proximity of trees to any property can help contribute to subsidence inadvertently.

The root structure of trees means that the roots grow in the surrounding area from the base of the tree.  These roots if near to your properties foundation could be damaging. Any damage or wear to a foundation increases the chance of subsidence in the property. This is due to the fact weakened foundations are not able to hold the weight and force of the property above them. Resulting in shifting foundations.

Don’t think I am attempting to scare you off buying a property with a tree on it, I’m not. I am instead attempting to ensure that you get a professional to assess the risk of damage to foundation and structures within proximity to the tree.

Poor Construction

Just like many latent defects poor construction of the property causes negative effects in the long run. Poor workmanship on all factors of the house such as quality of materials, structural design, lack of support and overall structural stability can contribute to subsidence.

Poor construction is not solely attributed to the actual contractors for the construction. Inferior quality materials are a major factor in poor construction. These materials are usually provided to many contractors so they are unaware of the exact quality of the materials. Low-quality materials such as weak concrete, rotten wood, and weak mortar all reduce the stability of the home. The change in structual stability just like all the other causes leads to weakened structures. Weakened structures are always more susceptible to subsidence.

Effects of SubsidenceSubsidence

Subsidence has a variety of effects on a structure from small issues such as ripple of wallpaper to extremes such as cracked windows.

Issues such as cracks in both interiors and exterior walls can occur as well as in ceilings. These cracks are both visually unappealing as well as contributing to the weakened structural integrity. Cracks in a structure reduce the value of a home additionally they increase the risk of structural damage. Door and window frames become warped in the corners causing doors and windows to ‘stick’ making them harder to use on a day to day basis.

Extreme cases of subsidence can occur under a range of circumstances. For example, if foundations are either extremely shallow or the material used to construct is subpar or if subsidence is left untreated.  Long-term structural weakness can result in windows cracking making them both unsafe to be near and additionally not as effective as insulation. In very few cases subsidence can cause small and/or poorly crafted properties to collapse.

For more information about subsidence from spotting signs to potential damage feel free to check out this website.