Across Kent
When to Act on Cracks and Movement in Your Home
Send a short description of what you have noticed. A specialist firm will read it and tell you whether the signs point to something that needs attention now or something they can watch over the coming months.
Why timing matters more than size
A hairline crack that appeared overnight after heavy rain behaves differently from one that has sat unchanged for five years. The width of a gap tells you part of the story, but the speed at which it opened tells you more.
Movement in a home falls into two broad categories. Some settling happens once and stops. Other movement repeats with the seasons or accelerates because something underground is failing. Knowing which category applies determines whether a house needs work this month or simply needs watching.
Rushing into repair before understanding the cause wastes money. Waiting too long when the ground is actively shifting lets a small problem grow into a larger one. The goal is to match the response to the rate of change.
Signs that usually need earlier attention
Certain patterns suggest the ground beneath a home is still moving. A crack that widens by a millimetre or more within a few weeks, doors that begin sticking in frames that worked fine last month, or gaps opening between skirting boards and floors all point to active movement.
Water escaping from drains is another prompt. Saturated soil under shallow foundations loses its bearing capacity quickly, especially on clay. If a drain runs close to the wall where cracking has appeared, a [drainage CCTV survey](/stabilising/drainage-cctv-survey) can rule out a leak before anything else happens.
Homes built on made ground, near old pits or on slopes above the coast face particular risks. In those locations, even modest new cracking justifies a [structural movement survey](/stabilising/structural-movement-survey). The surveyor measures how much displacement has occurred and whether it is continuing.
Signs commonly watched over time
Not every crack signals trouble. Plaster shrinks as it dries, and thermal expansion makes walls flex slightly between summer and winter. Fine lines around window corners or along the joints where an extension meets the original house often fall into this category.
When a crack stays the same width through a full wet and dry cycle, it has likely finished moving. Crack monitoring uses small gauges fixed across the gap to record any change over weeks and seasons. The readings build a picture without disturbing the wall.
Watching is a deliberate choice, not neglect. It prevents unnecessary work on a home that has simply settled. If the gauges stay flat after twelve months, most specialists consider the movement historic. If they creep open, the data shows exactly how fast and in which direction the fabric is shifting.
What happens after you describe the signs
The first step is always a conversation about what you can see. You describe the crack, its location, when you first noticed it and whether it has changed. That information shapes what comes next.
Sometimes the answer is to fit monitoring gauges and return in three months. Sometimes a drainage survey makes more sense if damp patches sit below the damage. In other cases, a full structural movement survey is the right starting point because the pattern suggests deeper ground failure.
If the findings show the home needs stabilising, separate specialist firms handle the physical work. Methods range from resin injection to firm up weak soil, to screw piling where access is tight, to traditional underpinning where foundations must be deepened. Each method suits different ground conditions and building types across Kent. The choice depends entirely on what the investigation reveals.
What to look for around your home
Movement leaves marks on the building fabric. Some appear suddenly after a storm or a dry spell. Others grow so slowly you only notice them when redecorating. Here are the things people tend to spot first.
- 1
Diagonal cracks in brickwork
Lines running at an angle through mortar joints, often wider at one end. They can follow seasonal moisture changes or signal deeper ground loss.
- 2
Doors and windows catching
Frames that jam or leave uneven gaps when closed. Wood swells with humidity, but persistent sticking may mean the opening has distorted.
- 3
Gaps at skirting boards
A visible space between the bottom of the wall and the floor trim. This sometimes appears when a floor slab drops away from the masonry.
- 4
Cracks in interior plaster
Fine lines radiating from ceiling corners or door heads. Many are harmless shrinkage, but widening ones deserve a closer look.
- 5
Sloping floors
A ball rolls across the room or furniture no longer sits level. Gradual tilt can indicate settlement beneath one side of the house.
Common questions about timing
Questions that come up regularly. For anything not covered here, send a description of what you see.
- How quickly should I get a crack looked at?
- If a crack has appeared in the last few weeks or is visibly widening, arrange a structural movement survey within a month. Hairline cracks that have not changed for a year or more can wait until your next decorating cycle.
- Does a small crack mean subsidence?
- Not necessarily. Most houses develop fine cracks as materials age and respond to temperature. Subsidence tends to produce diagonal cracking that widens at one end and correlates with dry weather or nearby tree roots.
- Will monitoring delay repairs I actually need?
- Monitoring takes three to twelve months because it tracks movement across seasons. If the ground is failing rapidly, a specialist will recommend immediate action instead. Monitoring protects you from paying for work your home does not require.
- Can a leaking drain cause cracks?
- Yes. Water washing soil away from shallow foundations is a frequent cause of localised movement. A drainage CCTV survey identifies fractures or blocked joints beneath the house before any stabilising work begins.
- Is underpinning always the answer?
- No. Underpinning is one option among several. Resin injection can firm loose ground without excavation. Screw piling works where access is restricted. The right method depends on the soil type, the depth of competent ground and the weight of the building.
- I am buying a house with cracks. What do I need?
- A home buyer subsidence report gives you a clear picture of past and present movement before you exchange contracts. It sets out whether the issue is historic, ongoing or likely to recur, so you can negotiate with facts.
Tell us what you have noticed
Write down where the crack is, how wide it looks and when you first saw it. A specialist firm will review the details and suggest whether to monitor, survey or act. There is no fee for this initial advice.
- No obligation to proceed
- Reviewed by a specialist firm
- Free initial guidance