Cracks and subsidence in a property, a cause for concern?

• Posted onJuly 10, 2023

If you are a homeowner, or looking to buy, the very word subsidence may fill you with dread or visions of sinkholes which hit the newspaper headlines. According to the British Insurance Brokers Association, subsidence is a common issue affecting an estimated 20 per cent of homes in some way. But what exactly is it, and should you be worried?

It is natural to be concerned if someone mentions subsidence, but most instances are at the less serious end of the spectrum. It is important to keep things in perspective, and your professional advisors can help you assess and manage any risks effectively.

WSP Solicitors are here to answer some of your questions.

What is the difference between subsidence and settlement?

Subsidence is when a building’s foundations move because the underlying ground conditions change. Typically, as the soil sinks this damages the property’s structural integrity and cracks appear as walls shift and floors drop.

Not all cracks in a building will be down to subsidence though. Some movement over time is normal, especially when a building is new. This is called ‘settlement’ and happens as the ground adjusts to a building. The underlying soil does not sink but becomes compressed under the additional weight. Settlement is not usually a problem because it does not affect the property’s integrity.

What causes subsidence?

Subsidence can be down to the type of soil a property is built on. Some soils, like clay, will shrink and expand with changes in their moisture content, especially in extreme weather like a flood or a prolonged heatwave. Nearby trees may exacerbate this problem, as during dry periods their roots extract more moisture from the soil, creating additional instability which can affect the soil supporting a building’s foundations.

Other causes include poor construction, previous mining activity, and water leaks, which can wash soil away from a building’s foundations.

How do I know if my home has subsidence?

Cracks in a wall are often the first signs of subsidence. If they appear suddenly or are more than 3mm wide, you should seek professional advice promptly. Otherwise, monitor the cracks carefully. If they do not change, this could be down to settlement.

Typically, subsidence cracks create a zigzag pattern which follows the mortar line in the brickwork. Other indicators include: sinking or sloping floors; misaligned windows or doors; ripping wallpaper which is not attributable to damp; noticeable leaning; or an extension which is cracking or breaking away from the main property. If you think your property may have subsidence, you should discuss this with a qualified surveyor. They may be able to reassure you or offer advice on how to fix the problem.

How do I know if the property I wish to buy has subsidence?

As a buyer, you will lack the detailed personal knowledge the seller has. Instead, you will have to rely on your own observations and your professional advisors.

Getting the right survey is very important. Remember, your lender’s valuation is not the same as a survey. A valuation may identify major structural issues, but its aim is to reassure your lender the property is sufficient security for their loan. To get a fuller picture, you should obtain a comprehensive survey from a qualified surveyor.

Your solicitor also has a key role to play in helping you assess the risk. Their conveyancing searches and enquiries may reveal whether subsidence is an issue or requires further investigation. For example, a standard search will establish if your property is in a coal mining area or affected by brine workings. A more comprehensive environmental search could show the wider potential for ground subsidence.

The property information form, which the seller completes, should also give details of any remedial works that have been carried out, like underpinning, as well as insurance or warranty claims. Further investigation should reveal the extent of any problem.

My home has subsidence, what can I do about it?

The most important thing is to get the right advice. A qualified surveyor can identify the cause of subsidence and how best to fix it, for example through removing any offending tree roots or underpinning. You should also check your insurance policy and any warranties, such as National Housing Building Council (NHBC) certificates. A claim under these could cover the cost of any necessary remedial works.

Many insurance policies cover the cost of repairing damage caused by subsidence, subject to an excess. However, they may not do so if your home has suffered from subsidence before. So, it is important to check your policy and to notify your insurers as soon as you know there is an issue.

Must I tell a buyer about subsidence when I wish to sell?

Despite the adage buyer beware, honesty is the best policy when it comes to subsidence.

Firstly, your buyer may discover the issue through their own survey and enquiries. Being upfront, rather than leaving your buyer to find out themselves, can build trust and good will. Secondly, the information you provide in the property information form must be correct. An answer which is wrong or misleading means you could be liable for misrepresentation. In a worst-case scenario, you may have to compensate the buyer for the difference in value.

If your home has had remedial work done, then providing details can reassure the buyer. This is especially so if there is a guarantee or warranty and you can assign the benefit to them. Likewise, a report or other evidence the subsidence is historic may allay concern.

In addition, a history of subsidence means your buyer may struggle to get insurance cover. Ensuring your policy does not lapse and transferring the benefit to them may be the most viable option; few buyers will buy a property they cannot insure.

The property I am buying has a subsidence issue, what should I do?

Talk to your professional advisors. Your surveyor can give you some idea of the likely physical impact, for example if the subsidence is historic then it may be of little effect in practice.

Sometimes, you will need to know more before you can make an informed decision. For example, if the seller’s answers to pre-contract enquiries reveal they, or a previous owner, has made a claim under an NHBC guarantee, your solicitor should make further enquiries. The outcome may reassure you, as remedial works may have corrected the problem. More rarely, those investigations may reveal an ongoing problem, or a situation which could worsen in the future. In that case, you may want to negotiate a price reduction to reflect the additional risk, require the seller to remediate, or decide to look for another property.

How we can help

Our conveyancing solicitors have handled the sale of many properties with a degree of subsidence, and there is usually a pragmatic remedy. We understand the key issues, and can keep your transaction on track even if it throws up some unexpected issues.

For further information, please contact on of our offices in Stoud or Gloucester on 01453 847200 or use the enquiry form on the side.