What is subsidence and other types of ground movement?


Subsidence is the downward movement of the site on which a building starts.  Where the movement is unconnected with the weight of the building. Simply put the soil beneath the building foundations is unstable.

This will differ from “settlement” which can also result in the movement of a building.  With settlement the building sink

subsidence the downward movement of the site would have occurred without the weight of the building.

There are other types of movement as well. Ground movement can impact the site on which a building stands and beneath its foundations.  Heave, landslip, settlement, and subsidence can cause damage to a property.

Insurance policies they often refer to “the site” when talking about movement cover.  This means the prepared ground, including made up ground. It may be on which a building is erected after the trenches have been dug. Firstly, it may be immediately prior to the first step in the actual process of the building.

Will my insurance company cover me for subsidence?

Yes, they would cover you for subsidence. There are different types of ground movement and four main causes.

For instance: –





These are defined as follows:-

Heave – upward movement of the ground beneath a building as the result of soil expanding

Landslip – downward moving of a sloping ground

Settlement – downward movement as a result of soil being compressed by weight of a building within ten years of construction

Subsidence. The ground beneath a building sinks, pulling the property foundations down with it. It usually occurs when the ground loses moisture and strength. It can be caused by a prolonged dry spell.  Trees and shrubs which can absorb significant volumes of water from the soil and cause it.

Subsidence – these cases can be complex and can require expert evidence and technical data.  They will need to look at the symptoms of the problem to find out why it is caused.

You would normally find that subsidence is caused by one of the following situations:-

Clay shrinkage

Clay shrinkage is one of the most common causes of subsidence.  This is made up of about approximately 30 to 35% water. Soil can with a high clay content dry out as a nearby vegetation sapping up water. This happens in the long hot summers.  The volume of the soil decreases and the buildings foundations subside.


Often a tree can cause structural problems to a property. This is due to shrinkage of the clay or subsoil beneath the foundations.

An insurance company will usually instruct a company to advise of the most appropriate remedy.  These are called arboriculture’s.  They may include cutting back down the tree to its trunk and topping it. They may require thinning or removing it. Look at installing root barriers to stop the encroachments of the roots.

Escape of water

Where there has been a significant time of escape of water from a bursting or leaking pipe. This can wash away fine particulars of underlying soil.  The soil beneath the property can reduce. This can cause the property foundations to subside.

An escape of water can cause the underlying soil often to soften. The whole property has less support and cause the foundations to subside.

It is often a case that this comes under an escape of water claim within the policy.  There can be specific exclusions for subsidence damage under this peril clause which could involve a higher excess.


Where there has been a collapse of underground mines even long disused mines.  This is a valid insured event, but you need to ensure that the property is not necessarily within a mining area. Did you disclose this when putting the insurance in place?

Poor Ground

Every property will take a period of time to settle.  This is due to the weight of the building compacting the soil beneath on its foundations.

Unfortunately soil can compact and this can exaggerate for instance:-

  1. Poor ground
  2. Inappropriate material used by the builders when making up the ground
  3. Lack of compaction of made up ground material
  4. The way the ground is prepared before the building starts

Any of the above can result in a considerable down movement of the property or floor slabs and damage the property.

It is important that you are aware of any of these circumstances before you take out the insurance policy and that you fully disclose them.

You may find that an insurance company asks you to fill out a specific subsidence questionnaire. This will ask certain questions. They can request this before they put you on cover.  Additionally, they will ask whether the buildings are built up on made up ground, landfill, or flag heaps.

Are there any visible cracks in the walls if yes please advise? –

  1. Between 1mm and 2.5mm wide
  2. Between 2.5mm and 5mm wide
  3. More than 5mm wide

Has the property for which insurance is required ever been damaged by subsidence? Heave, landslip, or movement? Any signs of repair?

Are there any trees or shrubs within 20 metres (65 feet) of the property? Are there any more than 5 metres (15 feet) in height?

If yes please indicate the distance of the nearest shrubs/tree from the building for example:-

  1. 10 to 20 metres (32 to 65 feet)
  2. Less than 10 metres (32 feet)

Has the property ever suffered from any problems with undergrown drainage?

If any of the answers to the above questions are yes, then you may have trouble trying to insure the building. You may get an increased excess for the policy.

Would I be covered for all the above?

Almost all commercial property insurance cover loss or damage by subsidence heave and landslip.  They usually cover the cost of repairing the loss or damage. They will not cover the cost of preventing further subsidence.

Repairing the damage to the building and super structure is covered but the cost of stopping the building from moving in the future is not.

If a building is still moving, you will usually need to carry out works to stop the movement first. You need to ensure that the repairs are effective and last for a reasonable period.

The insurance company will normally send a loss adjuster to identify the cause of the subsidence. They will ensure that it stops the effect on the property. This could by removing vegetation or repairing leaks on drains for example.

You will find that most building policies only the cost of repairing the damage caused by subsidence. They do not necessarily proactively prevent any future subsidence.

Stabilising the building?

When dealing with this so that the repairs are effective you will need to make sure that the property is stable.  This may not be covered by your insurance. It is needed to be dealt with straight away to stabilize the property. It may be needed to solve the immediate problem and to prevent any future subsidence.

Once the property has been stabilized repairs to the super structure can be carried out.  These can involve filling cracks and restoration begin.  However, it might even require masonry to be strengthened.


Underpinning if often seen as a permanent and effective way of stabilising a building. This is only used in the most serious of cases.  It is seen as a preventative measure which isn’t always covered by your insurance policy.  Therefore, you would need to check with your insurance company in this regard.

In many cases a building can be stabilized by other action for example:-

Firstly, repairing leak drains

Secondly, removing vegetation

Thirdly, removing other external causes

Lastly, providing additional strengthening

There are other ways of stopping it and you may need to consider these and what is adequate to stop the movement based on expert advice.

I have an existing subsidence issue from some time ago. What should I do?

Always disclose any form of previous problems you may have had with subsidence. This is actually critical when dealing with insurance companies.

You may find that the insurance company would not cover you for any previous work that has been carried out.

In relation to a claim for subsidence or heave every single property will be different. It is important that you are aware of any issues. Also these are fully disclosed.

Why not contact us on (01273) 827090 to discuss any requirements you may have. Click here for an instant quote.

With subsidence the downward movement of the site would have occurred without the weight of the building.

There are other types of movement as well but in real terms ground movement can impact the site on which a building stand. It could be beneath its foundations.  In addition heave, landslip, settlement and subsidence can cause damage to a property and upset its owners or occupiers.

In insurance policies they often refer to “the site” when talking about movement cover.  Therefore, this usually means the prepared ground, including made up ground, on which a building is erected after the trenches have been dug, and immediately prior to the first step in the actual process of the building.


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