Cracks can be commonly found in the walls of a house, often providing an indication that there may need to be a structural assessment undertaken. Finding cracks in your home can be concerning, that’s why we are here to help. In this article, we explain  when you may need to worry about house cracks, common reasons why your house could be cracking, if wall cracks indicate a structural problem, and where to get the best engineers  to undertake an assessment on your home. 

How can I self assess the cracking in my house walls?

Width of Cracks

Movement in the foundations of a dwelling generally create large stresses in building elements often leading to cracking. Crack widths between one and five millimetres are generally associated with normal household maintenance and can be monitored or further investigated to ensure the cracking is only superficial (AS2870 Residential Slabs and Footings).

Monitoring cracks in your house walls

With all cracking and separation it is recommended to consult a structural engineer to review the damaged noted and recommend the next stages forward. However, monitoring can be undertaken with cracking less than five millimetres through the following techniques:

  • Completing foundation maintenance as per the CSIRO information sheet. This information sheet is readily available on the web and outlines recommendations for general household maintenance to mitigate foundation movement.

  • Monitor the size of the crack by measuring the crack width and length with either a ruler or a measuring tape. This exercise at the same point of the crack periodically will determine if the crack is widening or getting longer and further movement is occurring. This can also be completed with a crack card as seen in the below photos.
Cracks In House Walls
Example of measuring the width of a crack
House Cracks When To Worry
Example of measuring the length of the crack

Cracks found larger than five millimetres should be investigated further and an Engineer should be consulted. 

Cracking in a home or the type of crack found doesn’t always mean there is a structural concern.   If you want peace of mind, give us a call and we can help determine if your crack needs to be monitored or an engineering assessment needs to be undertaken.

Why Is My House Cracking?

Even when they are well built by professionals, most buildings develop cracks during their lifetime. Here are some reasons your house may be cracking:

Initial Shrinkage

Building materials like concrete may shrink in the beginning. This shrinkage is irretrievable, and commonly found in concrete slabs. Shrinkage cracks in a building can be reduced at the time of construction through different techniques.

Broken Pipes or Poor Drainage

Broken pipes or poor drainage can lead to a localised area with high moisture. Depending on the founding soils this could lead to a shrink or swell of the soils. Generally, as the soils support the foundations of the dwelling any movement is mimicked leading to foundation movement and possibly cracking.


Trees in close proximity to a dwelling can cause abnormal moisture conditions or invasive roots can cause damage to the footings. Roots that grow under footings exert upward pressure on the footings as they increase in cross-sectional size, causing shrinkage or subsidence. Another common cause vegetation can have on shrinkage and subsidence are roots found in the vicinity of footings that absorb much of the moisture in the foundation soil. 

Natural Forces

Earthquakes, tremors, winds, rains, and flooding events can cause cracks in your building, which may occur due to a sudden shift in the lower layer of the earth. This might have happened because the void in the earth has collapsed and filled with soil from above.

Seasonal Changes

The type of soil on which the house is constructed may be subject to swelling and shrinkage due to the clay content. Substantial differential movement to the footings can occur due to the effects of seasonal changes in rainfall and droughts accordingly.

Do cracks in a wall indicate a structural concern?

A house wall crack is a possible sign of structural damage. This damage may be due to vibration, drainage problems, wind storms or expansive soil. 

Cracking is not always a structural concern. Commonly found in the window and door frames of a wall, seasonal expansion and contraction of wood framing are often contributing to the cracking found in a home. A possible indication that cracks may need  further investigation  can be when cracking is more than 5mm wide or your doors no longer close in the frame.

If this is the case, you may have a structural problem. If you have identified cracks in your home, we recommend having a JHA Engineer attend the property to undertake an assessment of the cracks and potential structural concerns. 

How to get help with a crack in your house wall

JHA Australia’s team are experts in the field of concrete slab lifting, foundation repairs, wall cracking, and ground stabilisation, helping determine the cause and solution to every building problem.

If you need a reputable team of engineers who are experts in this field, get in touch with us today. 


Our team of Engineers  are dedicated, highly skilled, and passionate about assisting you in achieving a smooth finish on all your plastering jobs. Our forensic engineering team can assess the cause of your building problem and provide solutions. We also have an experienced and professional design team who can provide you with the best structural design, assessment, and certification.

Contact us today for an answer to your questions and enquire about any of our services you may need.