Most houses develop cracks over time, this is a natural phenomenon, it can be a result of settling or something more serious. Knowing how to read and assess cracks in your house make it easier for you to take the right steps to deal with them properly.

Of course, if you are building a new house or undertaking extensive renovations it is time to consider using a polymer formwork system. It is strong and provides easy access inside the wall cavity, making it the perfect option for hidden cables and pipes. 

Types of Crack

There are several different types of cracks to be found in the typical house:

  • Hairline

Hairline cracks are usually defined as less than 1mm wide. They can run in any direction and are usually a result of the plaster or finishing material drying out. These cracks can be filled and, if necessary, painted. This will return your wall to like new. 

  • Small

Small cracks are usually defined as between 1mm and 5mm wide, they may vary in width and run in any direction. However, they commonly follow mortar lines and can be easily refilled and left. There is no concern about structural integrity with this type of crack.

  • Medium

Medium cracks cover anything between 5mm and 15mm. These can also go in any direction but they will need further investigation. In most cases, filling will resolve the crack but you need to have the issue assessed to ensure there is no underlying issue. With a crack this size, it is possible and you will need to have it dealt with by the professionals.  

  • Large

Large cracks are anything over 15mm and are often a sign that your house has a structural issue. You will need the cracks professionally examined and the possible solutions discussed.

It should be noted that cracks greater than 25mm are generally a sign of subsidence or structural collapse. You will need professional assistance to diagnose the issue but it is likely your home will need to be underpinned or even rebuilt!

Understanding Subsidence

Modern homes are built on a large slab of concrete, this gives a level and solid base for your house which helps the builders to create straight and strong walls.

However, the concrete is still sat on soil and, this can move over time. Heavy rain or leaks that constantly direct water to one area of the foundation can increase the likelihood of this happening. If the soil under moves then the foundation will develop a crack and the wall is likely to drop slightly. The severity of the drop will be shown by the size of the crack. 

Your house will then lose strength in one wall which can have a knock-on effect on the rest of the house. The result is a wall that needs to be underpinned or even taken down and rebuilt. 

If you have any concerns regarding your home it is a good idea to get the professionals in to assess it. They can advise you regarding issues and the best course of action to rectify the problem.