Crack investigation and engineering-led repair for cracks in walls, masonry and structures, the cause is diagnosed before any repair is recommended.
Most cracks in homes are cosmetic, but some are warning signs. Here is how to tell the difference.
The honest answer is that the majority of cracks in houses are not structural. Fine hairline cracks in plaster, shrinkage cracks in new render and small cracks around door and window openings are usually caused by normal thermal and moisture movement and are cosmetic.
Cracks are more likely to be serious when they are wider than about 3mm, run diagonally through brickwork in a stepped pattern, appear on both inside and outside faces of a wall, taper from wide to narrow, follow the line of a lintel or foundation, or, most importantly, are getting wider over time. Doors and windows that suddenly stick, or sloping floors alongside cracking, are further warning signs. If you see any of these, it is worth having the crack inspected. EMA Structures will inspect, diagnose the cause, and only then advise whether monitoring, repair or stitching is the right response. If the cracked property is one you are selling, a pre-sale structural review can settle the question before it is raised during the sale.
The classification determines the response, from redecoration to a designed repair.
Typically fine, stable hairline cracks in plaster, render or finishes caused by thermal movement, drying shrinkage or minor settlement. They do not affect the load-bearing capacity of the building and are usually addressed by filling and redecoration once confirmed stable.
Wider, often diagonal or stepped cracks linked to foundation movement, subsidence, overloading, lateral instability or corroding embedded metal. These affect the structure and need the cause diagnosed, the movement confirmed stable, and a designed repair such as crack stitching or foundation works.
Diagnosis identifies which of these is driving the cracking before any repair is specified.
Cause first, repair second, so the fix lasts.
Site inspection of the cracking, its pattern, width and location.
Identify whether the cracking is structural and what is driving it.
Monitor with tell-tales or readings where movement may still be active.
Prepare a repair strategy and specification with calculations where required.
Coordinate crack stitching, Helifix-type repairs or masonry works with trusted contractors.
Review the completed repair so it follows the engineering intent.
Crack repair sits alongside survey, subsidence and wider structural repair work.
Inspections and defect reports that diagnose cracking and movement.
Learn moreMovement and subsidence assessment, monitoring advice and repair strategy.
Learn moreEngineering-led repair strategy, specification and contractor coordination.
Learn moreA crack is more likely to be structural when it is wider than around 3mm, runs diagonally through brickwork or blockwork, follows the line of a lintel or foundation, tapers, appears on both faces of a wall, or is widening over time. Stepped diagonal cracking near corners and openings often points to foundation movement. Any crack that is growing should be assessed by an engineer.
Common causes include thermal movement and seasonal shrinkage, foundation movement or subsidence (often clay shrinkage or nearby trees), leaking drains washing out soil, overloading or removed support, sulfate attack, corroding wall ties or embedded steel, and lateral instability such as bulging or leaning walls. Diagnosis identifies which of these is responsible.
Crack stitching reinstates the tensile strength of cracked masonry by bonding stainless-steel helical bars (such as Helifix-type ties) into raked-out mortar beds across the crack. It is specified once the cause has been diagnosed and any active movement has stabilised.
Sometimes. Where a crack may still be moving, monitoring with tell-tales or measured readings over weeks or months shows whether movement is ongoing or has stabilised. Repairing an active crack before it stabilises usually leads to the repair failing, so monitoring can be a sensible step before committing to works.
EMA Structures diagnoses the cause, prepares the repair strategy and specification, and coordinates trusted contractors to carry out works such as crack stitching. We can also provide a specification for your own builder and review the completed repair.
Send us photos and a description and we will arrange an inspection, diagnose the cause and advise the right next step.