Cracks in walls, jamming doors and windows, sinking floors and paths can all be indicators of foundation subsidence in your home.

As a home owner, or someone who is responsible for a residential property, do you know what subsidence is, why it happens, how to prevent it or where to go for help if your house is moving?

Foundation subsidence is one of the most serious problems that can occur in a property. It will affect your home’s structure and any future sale value.

Subsidence, which is the gradual downward movement or sinking of an area of land, can affect any home. If your house is sitting on shifting ground then it can cause the property’s foundations to move making them unstable or weak.

House subsidence issues can often be related to extreme weather conditions, which impact the solidity of the ground that your house is on, putting the building’s foundations under extra strain.

Mainmark specialise in house levelling and lifting using sophisticated, non-invasive ground improvement techniques to lift and re-level, eliminating the need and the expense of more traditional invasive methods, which include ripping out and replacing the floor or demolishing and rebuilding subsidising homes.

To help you discover if the cracks in walls around you home could be due to subsidence, we’ve developed this handy tool. Visit our crack gauge page to download our FREE crack gauge and start measuring and monitoring the wall cracks around your home now!

Print-at-home crack gauge

Problems we solve

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Cracked Walls

Solutions for structural damage due to sinking foundations

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Foundation Subsidence

Solutions for shifting ground or erosion

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Jammed Doors / Windows

Solutions for unlevel homes due to foundation damage

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Sinking Floors

Solutions for subsidence under your home

What is subsidence and the causes?

Some homes are at a greater risk than others when it comes to subsidence. There are also many geological, man-made and seasonal impacts that can make your home more likely to experience subsidence:

Clay soil can shrink, crack and shift during hot, dry weather, making the ground very unstable and potentially cause sinking foundations

After a drought, properties may be at risk because the soil is much drier

Trees and shrubs can also be a factor, particularly if they’re close to property foundations. Some species absorb a lot more water, making the soil much drier

Older properties may have shallower foundations

Local mining activity is another major risk factor. Similarly, former quarry or pit sites can cause instability as fill material decomposes

Leaking drains and water mains can wash away or soften soil, causing it to compact under the weight of a home

Signs of subsidence

Damage caused by subsidence will often present itself as growing cracks in the walls and ceilings of a home, particularly around the windows and doorways. It is caused by ground movements that impact the building’s foundations. Other signs of subsidence can be concrete floors, pathways and driveways appearing to have sunk or have large crack form in them.

It’s important to examine each sign in detail before assuming the worst. Cracks often lead homeowners to suspect subsidence. If a cracked wall is caused by subsidence, it will generally be:

  • Thicker than a 10pence piece (more than 3mm)
  • Diagonal, and wider at the top than at the bottom
  • Visible both on internal and external walls
  • Found close to doors and windows
  • Wallpaper crinkling at wall/ceiling joins
  • Doors and windows no longer close in the frame
  • Cracks where an extension joins the house

Turning a blind eye to cracks in walls may mean you’re missing the warning signs for serious and ongoing structural damage caused by subsidence. Cracks in walls are common in buildings; though some are nothing to worry about, others can indicate a sinking or damaged foundation.

Can subsidence effect home insurance?

Subsidence is usually covered under your building’s insurance, however if you are searching for a new insurer then you may have to contact a specialist structural engineer to assess your home before you can obtain cover. Many standard insurers will refuse to insure a property with subsidence.

For properties with subsidence history, this is also the case, and if you are looking to buy a property, consult the surveyor’s report and look for mention of past subsidence issues.

Making a claim for subsidence

If you suspect your property has suffered from subsidence damage you must contact your insurer as soon as you possibly can.

Your insurer will most likely send an engineer out to assess the damage and try to locate the cause. If it’s minor cosmetic damage, and the cause can be easily identified, repairs can often start straight away and be pretty quick.

If the damage is more severe and ongoing then this will need to be monitored over a longer time period to correctly diagnose the issue.

Your buildings insurance policy will usually cover the damage caused to the structure of the property by subsidence. Damage to garden walls, fences, gates, patios, and driveways will not usually be covered, unless the damage occurred at the same time as the building damage.

If the damage to your home is so severe that the property is uninhabitable, your insurance will often cover the cost of alternative accommodation while repairs are being carried out.

Most insurers impose an excess – usually £1,000 – on subsidence claims.

How Mainmark can help

Mainmark’s ground improvement and house levelling methods can repair foundation subsidence in your home and are effective for fixing cracks in walls or re-levelling sunken floors in homes of any size.

The Mainmark team of experts will visit your home, assess the damage, and ascertain the cause. Our experienced engineers and technicians establish the best underpinning approach needed, creating a plan specific to the needs of your house.

Houses that need to be re-levelled often develop cracks in walls, which can occur internally and externally. These houses require their foundations to be lifted and re-levelled. As the building is re-levelled wall cracks generally close up, leaving only a little cosmetic crack repair, such as patching and painting, to deal with. Most importantly, structural damage is resolved, and the future of the house is sound.

Our cutting-edge solutions are the modern answer to traditional concrete underpinning and are likened to keyhole surgery. Our non-invasive, clean and time-efficient solutions are not just for concrete slab floors; we can raise and relevel strip footings, a range of slabs and we can fill voids under paths and driveways too.

Individual houses, terraced houses and apartment buildings alike can suffer from subsidence or settlement. Settlement of a floor slab or foundations, supporting the walls or structure of the building, often causes cracking in the brickwork walls or distortion of door and window openings.

Mainmark complete foundation and house levelling by injecting one of our structural resins or specialist grout into the ground under the building’s footings for foundation repair. We can stabilise the ground under foundations and lift the structure back to level, normally closing any cracks that may have formed.

This house lifting and re-levelling eliminates the need and the cost of ripping out and replacing the floor or demolishing and rebuilding brickwork walls, restoring value to the home. The work is carried out with the minimum of disruption to the occupant. In many cases the occupant can remain in the home.

As opposed to more traditional methods of underpinning buildings, our resin and grout injection methods are quicker and in most case done from the outside using 16mm (1.6cm) diameter tubes and if interior injection is required only a 6mm tube is used. The size of the tubes means that there is minimal intrusion into the property.

Benefits of Mainmark’s methods

Cracks in walls generally close

Jammed doors and windows are freed up

No mess – there is no concrete dust, water, or anything else to clean up

There is minimal disruption to the home owner

We don’t cause further damage to the house or garden

With simple jobs, residents can stay in the home and may not even need to move much furniture

Techniques are non-invasive: no floors are taken up or grounds excavated

Many simple, residential jobs are completed in just a day

The products and techniques we use have no negative impact on the environment