Subsidence and settlement often get confused. One is a serious structural defect that can cost thousands to fix. The other is a common type of ground movement that is found in lots of new build homes.
So, what is the difference between subsidence and settlement?
Settlement is downward movement caused by the weight of a new building compressing the soil beneath it in the first 10 years of construction. Subsidence occurs when the ground beneath a property’s foundation sinks downwards. Unlike subsidence, settlement is unlikely to affect the structural integrity of your home.
It’s important for homeowners to be able to distinguish between subsidence and settlement. Knowing the difference between subsidence and settlement cracks will enable you to act fast if you suspect subsidence and avoid expensive and time-consuming repairs down the line.
In this article, we look at the main differences between settlement and subsidence, including the causes, signs and how to fix them. We also look at whether your home insurance policy will cover any damage caused by settlement and subsidence.
For free insights on selling a property with subsidence, hit the red button below.
1. What is settlement?
Settlement is a downward displacement of the ground beneath a property caused by the weight of the building in the first 10 years of construction. The load of the building can compress the soil beneath it during and after the building construction.
Settlement of the foundation structure is considered normal and acceptable to a certain extent for many new build homes.
1.1 What causes settlement?
Although they’re both types of ground movement, subsidence and settlement are caused by different things.
Settlement can be caused by:
- Ground underneath the home compacting under the weight of the building. This can cause the house to move downwards, as it settles on its new foundations.
- Poorly filled sites prior to building. Sites are sometimes filled to make them level before the building commences. If the ground wasn’t sufficiently compacted before the home was built, this can cause excessive settlement.
1.2 What are the signs of settlement?
Whilst the “settlement window” technically lasts for 10 years, you can usually notice signs within the first 12 months of moving into a new build home.
The National House Building Council state in their guidance notes to cracking in homes that settlement cracks in walls can be vertical, horizontal or diagonal. Settlement cracks can also appear in floors. The cracks can vary in width but, if the widths are less than 2mm wide, they are unlikely to affect the structural stability of your home.
Settlement cracks tend to occur near windowsills, stairs and door frames. This is because the windows, stairs and doors are the structurally weak areas of the house and so are more prone to settlement cracks.
How common are settlement cracks?
It is quite common for minor settlement cracks to appear in the first 12 months of a new build home’s life. Minor settlement cracks are unlikely to affect the structural integrity of your home and can be fixed easily using a suitable filler, grout, caulk or sealant when you next decorate the house.
2. What is subsidence
Subsidence occurs when the ground beneath a property’s foundation sinks downwards without any imposed load. Walls and floors can shift and crack as the foundations of the property are no longer supported by the ground beneath.
Subsidence can ultimately compromise the structural integrity of your home. It can be expensive and time consuming to fix if left untreated.
2.1 What causes subsidence?
The most common causes of subsidence are:
- Clay soil. Clay soil shrinks during hot, dry summers and expands during wet weather. This can make the ground unstable and can cause the foundations of a property to shift.
- Tree roots. Large, thirsty trees planted close to a property can pull water from the ground, especially during particularly dry spells. This causes the surrounding soil to dry up and shrink.
- Water leaks, such as burst pipes. Damaged or leaking pipes and drains can soften and wash away soil from underneath a building's foundations.
2.2 What are the signs of subsidence?
The main signs of subsidence are:
- Large cracks in walls
- Doors and windows sticking and/or becoming misaligned
- Sinking and/or sloping floors
- Wallpaper creasing or rippling at joins with no signs of damp
- Extension cracking or moving away from main property
- Noticeable leaning of a house
Subsidence cracks vs settlement cracks
Settlement cracks can be vertical, horizontal or diagonal and tend to be less than 2mm wide (though they can vary in width). They are usually found near stairs, windowsills and door frames.
By comparison, subsidence cracks tend to be…
- Wider at the top and slimmer at the bottom
- Usually more than 3mm wide (thicker than a 10p coin)
- Diagonal in shape
- Usually found close to doorframes and windows
- Visible both internally and externally
Thankfully, subsidence cracks have the above recognisable characteristics, making them easier to distinguish from other cracks in your home.
If you’re in doubt, you should contact your insurer who will send out a professional structural engineer to diagnose the cause of the cracks.
3. What homes are prone to settlement?
Some degree of settlement is common amongst most new build homes, but it soon stabilises.
It is rare for settlement to affect the structural integrity of a building.
4. What homes are prone to subsidence?
Although it isn’t possible to accurately predict which houses will suffer from subsidence, there are certain factors that may mean your property is more prone to subsidence than others.
Your house may be at a higher risk of subsidence if any of the following apply:
- It’s built on clay soil.
- It’s built near mature, thirsty trees.
- It’s a Victorian or Edwardian house with shallow foundations.
- It has an extension built with a different foundation depth and building materials to your home.
- It’s located in a mining area.
- It has poorly maintained pipes, drains and gutters.
You can read more about the 6 most common causes of subsidence and how to reduce the risk here.
If you're trying to sell a house with subsidence, check out the free quiz we've designed to help you move forward:
5. Does house insurance cover settlement cracks?
Minor cracks caused by natural settlement will not be covered by your home insurance policy in most cases.
Loss or damage caused by settlement tends to be excluded from most home insurance policies. Make sure to check your policy wording so you are fully aware of any exclusions that may apply.
So, your home insurance policy won’t cover you for the cost of repairing any cracks caused by settlement. What about the residential property developer that built your home…?
5.1 New Build Warranty: Defects Insurance Period
If you have just moved into your new build and have spotted signs of settlement cracks, it is worth reading through your welcome pack and home maintenance guides. These guides will set out what is and isn’t covered by the “new build warranty”.
Your new build warranty offers you protection for 10 years, and covers any “defects” found once you’ve moved in. During the first two years (known as the “defects insurance period”) the new build developer is required to fix any defects found in the property.
Definition of “defects”
Keep an eye out for the definitions section, particularly the definition of “defects”. A lot of housebuilding companies will exclude minor settlement cracks from their definition of defects. This means that you will be responsible for repairing the cracks.
We’ve reviewed three of the home maintenance guides available on the following residential home builder’s websites to see if their two-year warranty covers damage caused by settlement. Here’s what we found:
- Taylor Wimpy: their two-year warranty does not cover any problems caused by the settling of your home, natural shrinkage or condensation.
- Barratt Developments: Cracks smaller than 2mm wide are classed as normal home maintenance and repairs would not be covered by your warranty. However, Barratt Developments state that if “cracks are more than 2mm wide, or 4mm on staircases, contact your New Home Customer Care team and we may be able to repair these under your warranty”.
- Bellway: Normal settlement and shrinkage cracks are not defined as a “defect” and are therefore not included in their two-year warranty.
If in doubt, you can contact the company’s customer care team to clarify what’s covered. They will either confirm that all damage caused by settlement is excluded from the warranty, or that they’d be willing to repair minor and/or larger settlement cracks that appear in the first two years.
After the defects insurance period, the warranty provider will only be responsible for fixing any major structural issues in the subsequent eight years. This is known as the “structural insurance period”.
6. Will my insurance cover subsidence?
Subsidence is covered by most home insurance policies, provided your property has not had problems with subsidence in the past. You will have to pay a subsidence excess when you make a claim. Most policies have an excess of around £1,000 for subsidence claims, but the exact amount will be set out in your policy schedule.
A good home insurance policy should cover you for:
- Cost of repair, up to the sum insured under the policy.
- Alternative accommodation if the property is uninhabitable when repair works are being carried out.
- Damage to surrounding structures, where the damage occurred at the same time and by the same cause as the damage to the property.
7. How to fix settlement cracks?
A settlement crack that is 2mm or less in width is generally regarded as cosmetic and shouldn’t affect your home’s structural integrity.
You can repair a minor settlement crack using a suitable filler, grout, caulk or sealant. Make sure to sand over the area before repainting to give a smooth finish.
If in doubt, speak with someone at your local DIY store who should be able to recommend a suitable product depending on the size and location of the crack.
You should wait at least 9-12 months before fixing any minor settlement cracks if the property is a new build. If you fix the cracks any sooner, it is likely that they’ll reappear as the house may still be settling.
8. How to fix subsidence?
There are several different ways to fix subsidence. The treatment method that’ll be right for you will depend on the cause and the severity of the subsidence.
The four most common ways to fix subsidence are:
- Tree maintenance or removal
- Repairing leaking or burst pipes
- Resin injections
The most expensive, invasive treatment is underpinning. Thankfully, less than 10% of properties suffering from subsidence need to be underpinned.
Learn more about each of the ways to fix subsidence in my article: Help, My House is Subsiding! How To Fix Subsidence [My Top Tips].
If you have a property with subsidence and are looking to sell, hit the red button below.
By Matthew Cooper, Co-Founder of Home Selling Expert