Total Home Inspections News

2 March 2023

What is considered a structural crack and what causes this?

Perth has a unique sandy soil composition, which will allow water to flow freely due to the larger particles, the smaller clay soil particles block this flow and so can be highly reactive. This means the soil structure changes in volume due to the fluctuating moisture levels, a bit like a sponge, leading to foundation movement and cracking in homes. Perth is often also exposed to significant weather events, such as storms and flooding, which can cause significant damage to a home’s structure too.

Other contributing factors can also include minimal earthwork compaction to the building envelope during construction, site drainage, and ageing/settlement of foundations. Poor construction practices such as inadequate materials or not following the proper building codes can lead to cracking throughout your home over time.

Also, as the home ages, issues related to the settlement of foundations can occur too. Settling is a natural process that happens over time, but it can be exacerbated by poor construction practices or soil movement.

Identifying the cause of the cracking is very important and requires many considerations including the age and construction of the building itself, any structural alterations such as extensions, additions, or even demolition works, compaction of foundation soils, and adjoining landscaping e.g. large trees next to exterior walls etc.

What should you do if you find cracks around your home?

Identify the cause of the cracking

Before you can begin to address the cracking, you need to identify the cause. This can be done by hiring a structural engineer or Perth Building Inspector to assess the home.

Address any underlying issues

Once the cause of the cracking has been identified, you can begin to address any underlying issues. For example, if the cracking is due to soil movement, you may need to carry out a soil compaction test to confirm if the soil is compacted correctly which may require the foundation reinforced or repaired.

Fill in cosmetic cracks

If the cracks are purely cosmetic, you can fill them in with a filler or plaster. This will help to improve the appearance of the home, but it will not address any underlying structural issues if they exist.

Monitor the cracking

It is important to monitor the cracking in your home to ensure that it does not worsen. Keep a record of the size and location of the cracks and check them regularly to see if they have grown or expanded.

Seek professional help

If you are unsure of how to deal with the cracking in your home, or if you suspect that it may be due to a structural issue, it’s best to seek the help of a professional. When assessing any cracks that have appeared inside or outside your home, it is essential to have them inspected by a structural engineer if they are wider than 5 millimeters.

The severity, extent, and pattern of cracking are also important. Cracks in masonry tend to be perpendicular to the line of force and cracking also tends to concentrate in areas of weakness such as at junctions of walls or between door and window openings.

It’s important to determine which direction the cracks are moving across your home’s walls. Vertical cracks that start close to the joining points of dry walling and the ceiling are usually caused by the settling of your home’s foundations after construction has been completed. In most cases, these cracks are not a serious issue, and will also normally not cost a lot to repair.

Wall cracks that are horizontal or at a 45-degree angle can indicate more serious issues such as potential foundation shift, water damage, and other structural problems. If ignored, they will worsen with time and require expensive repair work to be done.

Cracks that run laterally can have several different causes but usually aren’t related to any significant structural problems. If there are cracks in your home that are running diagonally, these should be attended to immediately, as they can indicate subsidence of the slab or footings of your home.

Cracks often need to be monitored over time to determine whether they are stable (Not getting bigger or smaller) or changing. This monitoring should continue even after diagnosis right through to post-remediation to measure its effectiveness and adjust it accordingly. If cracking affects the functioning of the building e.g. waterproofing is compromised or doors and windows are sticking, this damage will also need to be repaired once the underlying issue is resolved.

Cracking can be caused by a variety of factors and it’s important to identify the cause of the cracking and address any underlying issues to prevent further damage. If you are unsure of how to deal with the cracking in your home, seek professional help to ensure that the issue is addressed properly. Engaging an independent Perth Building Inspector to assess the situation can help put your mind at ease. We can identify any real issues and give you a better idea of the extent of the damage. We can also offer advice or recommendations as to how best to tackle the problems.