Houses need continuous care and repair but at the sight of a crack in the walls, most people panic. Cracks in the internal and external parts of the building are 2nd most found building defect in Australia. More than 41% of houses inspected have been found to carry cracks in the internal or external parts of the property. (Read about 15 most found defects in the building inspection)

Fortunately, most of the cracks in a house are normal, even in new houses. Cracks are simply a sign of settling of the house. Other reasons for the cracks are changes in the temperature, changes in humidity, and vibration from the traffic.  But some cracks are deeper and longer which may be due to some issues underneath. Major cracks are costly to fix or may make your home uninhabitable.

So it is highly recommended for homebuyers to get a building inspection done for a complete assessment of cracks in the house. Only a competent building inspector can differentiate between major and minor cracks with certainty.

Building Inspection Council has compiled the scenarios when the cracks in the walls should be considered serious.

1. When the cracks are wide enough

Cracks More Than 5mm Wide

Any cracks which are under 5mm are not concerns for the stability of the house and are due to contraction and expansion of the plaster.

The cracks start to raise serious concerns when these are wide between 5mm to 15mm (up to 1/2 inch).  A crack of 25mm wide or more should be considered severe as it could be due to substantial structural damage, water damage, subsidence (sinking of footing or foundation), etc. A crack this wide needs an immediate response in terms of underpinning to ensure stability.

2. When the cracks run diagonally

Superficial vertical cracks are presentDiagonal Crack in every house and are not a reason for worry. This happens due to the expansion of plaster in humidity and contraction when drying up. These cracks can be easily fixed by filling and repainting.

However when the cracks are diagonal or in form of stairs moving up the walls then it is a matter of concern. These cracks are indications of serious problems such as foundation damage or foundation movement. You should get a thorough building inspection done to learn about the seriousness of the issue.

3. When the cracks are located above door frames

Cracks on the Top of Door Frame

The cracks will start to appear in the weakest area of the walls such as around the doors or window frames.  The window frames weaken the walls slightly and cause cracks. These cracks are normal and not a reason to worry.

However, when the cracks appear on the top of door frames and run in a diagonal direction, this is an indication of serious issues such as foundation damage or foundation shifting.

4. When you can see daylight through the cracks

Through Wall Crack

When there is a crack through which sunlight comes through or you can see through then this is a matter of concern. This is because the whole wall is shifting and not just one side of it. Usually, most of the cracks are visible only from one side and not from the other side. But when a wide crack appears that go through the whole house, it means the problems of subsidence.

As discussed, the cracks in the walls can be due to serious underlying issues. These issues may be costly to repair or make your house uninhabitable An expert building inspector can tell the difference between minor crack or major crack with precision.

Building Inspection Council is a not-for-profit organization and we provide free quotes to Australian property buyers from the pre-verified local building inspectors. The best thing about being a not-for-profit organization is that we do not have to compromise for profit and you get the most honest and genuine building Inspection quotes. CLICK HERE FOR 3 FREE QUOTES

For more information about defects and cracks in walls, you can read

Most Common Building Defects

3 Top Building Defects

15 Most Found Building Defects in the Building Inspections