Yes, as a homeowner you can carry out a basic visual inspection of your brick veneer cladding to identify potential movement cracks — and knowing what to look for can help you catch problems early before they become costly repairs. That said, interpreting what those cracks mean and assessing structural risk is a job for a qualified building inspector or Licensed Building Practitioner.
What Is Brick Veneer and Why Does It Crack?
Brick veneer is a single skin of bricks attached to a timber-framed wall with metal ties, leaving a cavity between the bricks and the frame. It is one of the most common cladding types in New Zealand homes, particularly those built from the 1960s onwards. Because the brick skin and the timber frame can move independently — due to temperature changes, moisture, ground movement, or foundation settlement — cracking is relatively common. Not all cracks are serious, but some can signal significant structural or weathertightness issues.
Types of Movement Cracks to Look For
When walking around your home, look for the following crack patterns:
Stair-Step Cracks
- These follow the mortar joints in a diagonal stair-step pattern.
- Very common and often caused by differential settlement (one part of the foundation moving more than another) or soil shrinkage in dry conditions.
- Fine stair-step cracks (under 2 mm wide) may be cosmetic, but wider or growing cracks warrant investigation.
Horizontal Cracks
- Run along mortar joints parallel to the ground.
- Can indicate lateral pressure from soil or a problem with wall ties, which is a more serious concern.
- Horizontal cracks near the base of a wall deserve prompt professional attention.
Vertical Cracks
- Run straight up through mortar joints or through bricks themselves.
- Often appear at corners, window and door openings, or where different materials meet.
- Can result from thermal expansion and contraction, or from the timber frame shrinking as it dries out.
Diagonal Cracks from Openings
- Diagonal cracks radiating from the corners of windows or doors are a classic sign of lintel movement or differential settlement.
- These are worth monitoring closely.
How to Inspect Your Brick Veneer
- Walk the perimeter of your home in good daylight, ideally after dry weather so the surface is clean.
- Look at mortar joints as well as the face of bricks — cracks often start in the mortar before spreading into bricks.
- Check around openings — windows, doors, and meter boxes are common stress points.
- Look at corners and junctions where the brick meets other materials such as timber weatherboards or soffit linings.
- Note the width and length of any cracks. A simple guide:
| Crack Width | General Indication |
|---|---|
| Less than 1 mm | Likely cosmetic/shrinkage |
| 1–5 mm | Monitor; may need investigation |
| 5–15 mm | Significant; get professional advice |
| Over 15 mm | Serious; seek urgent assessment |
These are general guides only — crack width alone does not tell the whole story. Pattern, location, and whether the crack is active (still moving) all matter.
- Mark cracks with a pencil line and date across the crack ends. Check back in four to eight weeks to see if the crack has grown — this tells you whether it is active or dormant.
- Look for associated signs of trouble: efflorescence (white salt deposits), damp patches on interior walls, doors or windows sticking, or gaps opening between the brick and window joinery.
What Causes Movement in NZ Homes?
- Seismic activity — New Zealand's earthquake-prone environment means ground movement is a real factor. MBIE Building Performance provides guidance on earthquake-prone buildings.
- Foundation settlement — especially on clay soils that shrink and swell with moisture changes.
- Corroded or missing wall ties — ties can rust over time, particularly in older homes, reducing the connection between the brick skin and the frame.
- Thermal movement — bricks expand in heat and contract in cold; without adequate movement joints, cracking can result.
- Moisture-related timber shrinkage — the timber frame behind the brick can shrink as it dries, causing the cladding to move.
BRANZ has published research on brick veneer performance in New Zealand conditions that is worth exploring if you want to understand the technical background.
Safety Note
When inspecting your brick veneer, do not attempt to climb ladders to inspect upper-storey brickwork unless you are confident and have appropriate equipment. Falls from height are a leading cause of serious injury. For anything above single-storey, engage a professional. Refer to WorkSafe NZ for safe working-at-height guidance.
When to Call a Professional
While a basic visual check is well within a homeowner's ability, you should engage a qualified building inspector or Licensed Building Practitioner if you notice:
- Cracks wider than 5 mm or that are growing over time.
- Horizontal cracks anywhere in the veneer.
- Multiple cracks appearing after an earthquake or significant weather event.
- Interior damp patches or mould that may suggest the brick veneer is no longer keeping water out.
- Bricks that are bulging, leaning, or feel loose.
- You are buying or selling a home — a pre-purchase inspection is strongly recommended.
A professional inspector can assess whether cracks are cosmetic or structural, check wall tie condition (sometimes using specialist equipment), and advise on remediation. You can find qualified local building inspectors and Licensed Building Practitioners on tradedirectory.co.nz.
Depending on the extent of any repairs needed, a building consent may be required. Always check with your local council — some repair work may qualify as exempt under Schedule 1 of the Building Act, but your council is the right authority to confirm this.
Licensed Building Practitioner (LBP)
BCITO Qualified
