Wall cracks are a common issue in Adelaide homes, just like in homes everywhere else. They can appear suddenly or develop slowly over time. Some cracks are purely cosmetic, while others can indicate foundation issues.
In this article, let’s discuss the different types of wall cracks, what causes them, and how to prevent them.
Different Types of Wall Cracks
Not all wall cracks are the same. Surface-level cracks are just cosmetic and don’t cause any damage to your property. You should only worry about deep or structural cracks.
Hairline Cracks
These cracks are very thin, usually less than 1 mm wide. Hairline cracks typically show up because of paint shrinkage, temperature changes, or minor natural settling of the house. They are common in new homes and are only cosmetic. Just make sure that they aren’t getting larger.
Vertical Cracks
Vertical cracks either run straight up or down and are caused by minor foundation movement or shrinkage in the concrete. They usually appear near doors, windows, or sometimes even in the middle of walls. These cracks aren’t serious unless they widen beyond 3 mm.
Horizontal Cracks
Horizontal cracks are more serious as they indicate pressure from the surrounding soil or significant foundation movement. They usually keep expanding, so don’t ignore them.
Diagonal Cracks
These cracks run at an angle because of uneven settling. If one part of your home’s foundation sinks lower than the other, diagonal cracks appear. They can also occur because of tree roots, poor drainage, or changing soil. Diagonal cracks are often cosmetic and easy to repair.
Step Cracks
Step cracks show up along mortar joints in brick walls in a step-like pattern. They indicate surface shrinkage or shifting soil under your home. Step cracks are cosmetic, but fix them early as they can significantly affect the look.
Spider Web Cracks
These cracks look like fine lines on plaster or paint that’s caused by surface shrinkage or poor plastering. Spider web cracks are just unsightly, not structural, but fix them early so they don’t worsen.
Read More: How to Fix Cracks in Concrete?
Common Causes of Wall Cracks in Adelaide Homes
Adelaide’s unique climate and soil conditions make homes here more prone to cracking. Here are the most common causes:
Foundation Settlement Cracks
Adelaide has clay soils, especially around the northern and eastern suburbs, that expand when wet and shrink when dry. This puts a lot of pressure on your home’s foundation. When the ground beneath your house shifts, the foundation can sink or rise unevenly, which causes cracks in both interior and exterior walls.
You can prevent foundation settlement cracks by keeping the soil around your home moist. Regularly water the ground around your foundation when it’s dry.
Thermal Movement Cracks
Adelaide experiences hot summers and cold winters, which causes the building materials to expand and contract. This repeated movement can cause cracks along joints, corners, or ceilings.
Flexible joint sealants and high-quality paint can help prevent thermal movement cracks to a great extent.
Moisture-Related Cracks
Excess moisture from leaky gutters or poor drainage can weaken your wall materials and cause plaster to bubble and crack. It can also cause joint movement as the timber frame swells and shrinks.
Inspect your gutters, roof, and plumbing at least once a year for leaks. Stormwater drains should be clear and slope away from your home. And make sure your downspouts direct away from the house so they don’t oversaturate the soil.
Poor Construction or Materials
Some wall cracks are also caused by using low-quality materials or poor workmanship. If the builder didn’t properly prepare the foundation or used low-quality mortar, wall cracks can appear.
These cracks usually reappear even after you repair them, so make sure to work with experienced and licensed contractors when building or renovating your home and use high-quality materials.
Other Causes of Wall Cracks in Adelaide Homes
Besides the factors listed above, here are some other causes of wall cracks in Adelaide homes:
- Tree roots: You should never plant large trees too close to your home, as they absorb moisture from the soil and cause it to shrink, which can lead to foundation movement.
- Vibration: Nearby road or house construction can cause small structural shifts.
- Renovation: Removing load-bearing walls without properly assessing the structure can cause stress cracks.
- Age of the building: Materials in older buildings naturally degrade over time, which can cause cracks. Minor movements in the foundation and structure can also start forming visible cracks.
Crack Prevention Tips for Homeowners
Here are some tips to prevent cracks in your home:
- Water the soil around your home regularly, but don’t soak it.
- Clean your gutters and downspouts at least twice a year.
- Inspect your gutters, downspouts, and roofs for leaks at least once a year.
- Plant large trees at least 25 meters away from your home. If you don’t have that much space, it’s best to stick with smaller trees.
- Use weatherproof sealants around doors, windows, and expansion joints to prevent water from seeping in.
- Use dehumidifiers or exhaust fans in bathrooms or the basement to prevent internal plaster cracks.
- When renovating your home, use flexible render or plaster that can handle minor movements without cracking.
Read More: Wall Crack Types in Adelaide Homes
Importance of Early Intervention
Fixing cracks early can save you a lot of money. A small hairline crack doesn’t look serious at first — in fact, it isn’t. However, if it’s widening or spreading, you need to look into it so it doesn’t turn into an expensive repair.
Larger cracks can lead to structural instability, leaking walls, and damaged plaster. They can also reduce the resale value of your property.
Learn More About Crack Repair in Adelaide
FAQs
Are all wall cracks serious?
No, many cracks are just surface-level and cosmetic. They occur because of shrinkage or temperature changes. However, deep or growing cracks can indicate foundation issues and should be inspected by a professional before they turn into expensive repairs.
What’s the difference between structural and non-structural cracks?
Structural cracks are usually wider than 3 mm and affect the stability of your home. Non-structural cracks are surface-level and cosmetic.
Should I fill in the cracks myself or call someone?
You can fill small hairline cracks with a patching compound, but if the crack keeps growing, it’s best to call a professional.
How can I tell if my foundation is moving?
Diagonal cracks above windows, doors that no longer close properly, gaps between walls and ceilings, and uneven floors are all signs that your foundation is moving.
How often should I inspect my walls for cracks?
It’s best to inspect your walls for cracks every six months. You should also check them after heavy rain or during a long dry period.
When to Call a Professional
If the crack is widening, expanding, or is deep into the surface, you should call in the pros to inspect and fix it. Don’t keep ignoring them, as they can lead to costly repairs down the line.
Swart Plastering offers concrete repair and restoration services to homeowners and businesses throughout Adelaide. With over 100 years of award-winning experience, our team can help you with everything from minor repairs to full-scale restoration. We use durable repair compounds, sealants, and coatings for long-lasting results.
