This is not an exhaustive or a complete subject. It is likely to change over time, with edits, additions and deletions, and is simply a collection of my thoughts based on many years of experience. You should follow your instincts, and you must always seek your own professional advice.
Buying a House with Cracks or a History of Subsidence – Should You Be Worried?
A crack in a wall does not necessarily mean subsidence.
Buildings move. New extensions settle, plaster shrinks, different materials expand and contract at different rates and older houses in particular can have cracks that have been there for decades without causing any significant concern.
But some cracks do matter.
And if you are thinking of buying a house with significant cracking, or one that has previously been the subject of an insurance claim for subsidence, it deserves considerably more investigation than simply being told “it was dealt with years ago.”
Why this matters particularly in 2026
The exceptionally hot and dry weather experienced during the summer of 2026 has once again brought subsidence into focus.
Subsidence is particularly associated with shrinkable clay soils. During prolonged dry periods these soils can lose moisture and reduce in volume. Trees and large shrubs can make the situation considerably worse by extracting moisture from the ground.
If the foundations of a building are shallow – as they frequently are in older houses – movement of the ground can result in movement of the building above.
Other causes are possible too. Leaking drains, defective water supplies, poorly compacted ground, historic mining and local ground conditions can all contribute to structural movement.
The important point is that the crack is the symptom. The real question is what caused it.
Not every crack is subsidence
This distinction is important.
I regularly inspect buildings containing cracks which are not particularly worrying. A fine crack between an extension and the original house, for example, may simply reflect the different ages and forms of construction.
Conversely, certain patterns of cracking warrant much closer investigation.
Diagonal cracking around windows and doors, cracks which continue through both the internal and external faces of a wall, distortion of openings, sticking doors or windows and cracks which appear to be increasing in width may indicate more significant movement.
The location, direction and age of a crack can often tell us considerably more than its width alone.
A competent building survey should therefore look at the whole building, rather than simply measuring an individual crack.
“There was subsidence, but the insurance company dealt with it”
I hear variations of this quite regularly.
It sounds reassuring, but as a purchaser I would want to know considerably more.
When did the movement occur?
What caused it?
Was the cause actually established?
Was the building monitored and, if so, for how long?
Were trees implicated and what happened to them?
Were drains investigated?
Was the property underpinned or were the repairs simply cosmetic?
Who designed and supervised any structural work?
Are there engineering reports, monitoring records, drawings, invoices and completion certificates?
Was the insurance claim formally closed and what exactly did the insurer conclude?
Most importantly:
Has the underlying cause genuinely gone away?
A crack can be repaired relatively easily. That does not necessarily mean that the cause of the crack has been removed.
A previous subsidence claim changes the conversation
This is where I believe purchasers need to be particularly careful.
A house which has suffered genuine subsidence is not necessarily a house which should never be bought. Many properties have been successfully repaired and remain perfectly serviceable buildings.
But neither should a previous subsidence claim simply be dismissed as ancient history.
You are not only buying the building. You are potentially acquiring its insurance history as well.
That can affect the availability of buildings insurance, the premium, the subsidence excess and potentially your ability to change insurer in the future.
It can also become relevant when you eventually come to sell the house.
The fact that the present owner has insurance does not automatically mean that you will be offered insurance on identical terms.
For that reason, I would strongly recommend investigating insurance before exchanging contracts, rather than assuming that suitable cover can be arranged afterwards.
Tell the insurer or broker the full history and obtain confirmation of the terms upon which they would be prepared to insure the property.
Do not rely simply upon a verbal assurance from the seller or estate agent that “insurance has never been a problem.”
What about underpinning?
Underpinning is sometimes presented as the ultimate reassurance:
“It was underpinned, so it can’t move again.”
Unfortunately, it isn’t quite that simple.
The important questions are why underpinning was necessary, which parts of the building were underpinned, what method was used and whether the original cause of movement was properly understood.
In some circumstances a properly designed underpinning scheme can provide considerable reassurance. But underpinning is still an important part of the history of the building and should be properly investigated.
I would want to see the structural engineer’s information and completion documentation rather than simply being told that underpinning took place.
What should you do before buying?
If I were advising a purchaser considering a house with significant cracking or a known history of subsidence, I would normally suggest three parallel investigations.
First, investigate the building.
Have an appropriate building survey undertaken by somebody experienced in diagnosing structural movement. Depending upon what is found, advice from a structural engineer may also be appropriate.
Second, investigate the history.
Ask your solicitor to obtain the complete documentation relating to previous movement and insurance claims. Ideally this should include the original investigation, monitoring information, engineering reports, details of repairs and correspondence confirming how the claim was concluded.
Third, investigate the insurance.
Speak to an insurer or specialist insurance broker before you become legally committed to the purchase. Explain the history fully and establish whether appropriate buildings insurance will be available, at what cost and with what subsidence excess and exclusions.
These three questions are related, but they are not interchangeable.
An engineer saying that the building is currently stable does not guarantee that an insurer will offer ordinary terms.
An insurer agreeing to provide cover does not prove that the building has no structural problem.
And a historic insurance claim marked “settled” does not, by itself, answer either question.
Equally, a recently settled insurance claim does not, by itself, offer reassurance either. You won’t have the important evidence of time to demonstrate that the problem won’t reoccur.
Should you walk away?
Not necessarily.
There are houses with a history of subsidence which I would be perfectly comfortable advising a client to purchase.
There are others where I would be extremely cautious.
The difference is usually the quality of the evidence.
If the cause was clearly identified, appropriate remedial work was undertaken, subsequent monitoring demonstrated stability, good records survive and satisfactory insurance can be obtained, the history may be manageable.
Where the cause remains uncertain, documentation is poor, significant cracking remains visible, movement may be continuing or insurers are reluctant to provide normal cover, the risk is very different.
And remember that you may have to explain exactly the same history to another purchaser when you eventually sell.
My advice: investigate first, decide afterwards
Subsidence is an area where reassurance should be based upon evidence rather than assumption.
Don’t panic because you have found a crack.
But equally, don’t allow a significant crack to be dismissed as “just settlement” without understanding why it is there.
And if the property has a known history of subsidence, don’t assume that because somebody else’s insurance company dealt with a claim ten or twenty years ago there is nothing further to consider.
Ask questions. Obtain the paperwork. Get appropriate professional advice. And establish the insurance position before you exchange contracts.
A house with a history of structural movement may still be a perfectly sensible purchase.
But it is one where you should understand exactly what you are buying.
Disclaimer: Anything posted in this Blog is for general information only and it is not in any way intended to provide any advice, legal or otherwise, on any general or specific matter that you can rely on. You should always seek your own legal and surveying advice.