Spotting a crack in your wall can be quite a scary experience. Don’t panic, but do investigate. Only a small proportion of cracks are symptomatic of a more serious underlying structural problem, however it is important to get them checked.
There are lots of possible causes for cracks in walls – some are simply aesthetic problems that can be easily fixed, but some could be symptomatic of a more serious underlying problem. Therefore, it is important to know what causes cracks in walls and whether you should be concerned.
This blog provides information around determining the type of crack you have, whether you should be concerned, and what course of action to take to ensure the safety of your property.
Causes of Cracks
Over time, structural damage is not uncommon in older properties. However, even newer properties can develop problems in the brickwork and masonry in certain circumstances. Simply put, cracks in walls occur when something has moved. This could be as minor as plaster drying, or the walls expanding and shrinking in response to the weather conditions.
Larger cracks or ones that develop rapidly could be the sign of a serious structural problem, like damage to the foundations or subsidence issues.
Subsidence is when the ground beneath a property sinks, causing the foundations to move with it. Subsidence can cause the building to shift, making it unstable and creating large cracks in the walls.
Other causes may include the corrosion of wall ties; temperature changes and changes in humidity levels; tree roots and road traffic vibration – among other structural and environmental factors.
Types of Cracks
Singular hairline cracks on interior walls should not cause too much concern. In these cases, you can simply fill with spackling paste, allow to dry and then repaint. However, if there are several around a central point, it will need further exploration.
Cracks will generally appear in the weakest areas of the wall, such as around a window frame. This is usually because a window compromises the strength of the wall slightly, causing cracks to appear. These aren’t usually anything to worry about, however a crack at the top of a door frame, or one that extends diagonally from the corner of a door can indicate more serious issues.
A quick, telltale sign as to whether a crack in a wall is serious is whether it is more than ¼ inch wide and has grown over time. In this instance, you should consult a structural engineer to determine the cause.
The presence of large horizontal or diagonal cracks are more concerning, however, and should always be checked by a professional. Any cracks that are on an exterior wall should always be investigated as it may be a sign of structural issues. They can also be an entry point for water and be likely to cause damp problems in the future.
Types of Structural Repairs
Peter Cox offers a number of structural repairs, including crack stitching, lintel repairs, structural anchoring, and cavity wall ties.
Crack stitching is a permanent and cost effective method of structural repair for fixing cracks in brick/stone walls and for properties suffering from cracks in the masonry and in the mortar bed joints. ‘Stitching’ cracked brick walls requires using bars grouted (a fluid form of concrete) into the bed joint, overlapping the crack in the wall, in the same way you would use thread to stitch two pieces of cloth together.
If a property is suffering cracks above or below openings, such as windows or doors, then it could suggest a weakening of the lintel that needs to be repaired. Similar to crack stitching, repairs carried out using lintel reinforcement prevent the potential collapse of the external outer masonry, provide resistance against further cracking, and strengthen the structure of the masonry.
A wall tie is used to connect two single leaf brick walls together as part of an external wall – with the performance of it crucial to the overall stability of the wall, wall tie failure is only visible once the effects of corrosion cause cracking to the internal and external walls. Millions of homes and properties across the UK suffer from either wall tie corrosion or wall tie failure and require structural repairs or specialist remedial wall tie replacement. More often than not the problem is that during building there have been insufficient wall ties installed.
Structural anchoring and reinforcement systems can be used as sympathetic solutions for larger structures, including historical buildings, masonry bridges, monuments, railway structures and walls. The installation process begins with drilling installation holes in the masonry and then inserting an anchor, before injecting the grout and filling out the cavity that’s been drilled. Drilling holes are then covered with the cores removed, meaning that the repair will be almost invisible.
Prior to any repair work taking place, it is essential the cause of the crack is first established. If you are not an expert yourself, we would suggest you contact a qualified individual such as a structural engineer or ourselves at Peter Cox to inspect the property and recommend the best course of action.
We recommend visiting Peter Cox’s dedicated web pages on Crack Stitching, Lintel Repairs, Structural Anchoring and Cavity Wall Ties. From there you will find more information regarding the work needed to repair the structural issue.