Yes, you can carry out a careful visual inspection of your home after an earthquake — and doing so promptly is a sensible first step. However, a DIY check has real limits. Structural damage is not always visible to the untrained eye, and some damage only becomes apparent days later as the building settles. For anything beyond a basic look-over, you should engage a qualified building inspector or structural engineer.
Stay Safe Before You Start
Before you inspect anything, make sure it is safe to re-enter. If you smell gas, see sparks, or notice the building is leaning or has major visible collapse, do not go inside. Contact your local Civil Defence authority and follow their guidance. WorkSafe NZ has useful guidance on hazard identification after emergencies, including the risk of falling objects, broken glass, and unstable structures.
Once authorities have confirmed it is safe to enter, keep your inspection brief and methodical. Take photos of everything you find — these will be essential for insurance claims and any professional assessment.
What You Can Check Yourself
A careful homeowner can identify many visible signs of earthquake damage. Work through the following areas systematically:
Outside the House
- Foundation: Look for new cracks, crumbling concrete, or sections that appear to have shifted or settled unevenly.
- Walls: Check for diagonal cracks at corners of windows and doors — these are a classic sign of racking (the building twisting under lateral load).
- Chimney: Brick chimneys are particularly vulnerable. Look for cracks, leaning, or missing mortar. A damaged chimney is a serious hazard and should not be used until inspected.
- Roof: From ground level, check for displaced or missing roofing material, sagging ridgelines, or gutters that have pulled away.
- Retaining walls and paths: Cracking, leaning, or displacement can indicate ground movement or liquefaction beneath.
Inside the House
- Ceilings and cornices: Fresh cracks, sagging plasterboard, or fallen cornice are common after shaking. GIB plasterboard systems can crack at joints even when the structure beneath is sound, but widespread cracking warrants professional review.
- Walls: Diagonal cracks running from door and window corners are more concerning than hairline vertical cracks in plaster.
- Floors: Walk carefully and feel for new bounce, unevenness, or areas that feel soft underfoot — these can indicate subfloor damage.
- Doors and windows: If doors or windows that previously opened freely are now sticking or won't close, the frame may have racked.
- Pipes and fittings: Check under sinks and around the hot water cylinder for leaks. Do not use the gas until it has been checked by a licensed gasfitter registered with the Plumbers, Gasfitters and Drainlayers Board.
Crack Severity: A Simple Guide
| Crack Width | Likely Significance | Action |
|---|---|---|
| Hairline (< 0.2 mm) | Often cosmetic | Monitor; repair when settled |
| Fine (0.2–1 mm) | Minor movement | Document; professional review if widespread |
| Moderate (1–5 mm) | Possible structural concern | Get a building inspection |
| Wide (> 5 mm) or stepped | Significant structural movement | Do not occupy; call a professional immediately |
These are general guides only — location and pattern matter as much as width.
Liquefaction and Ground Damage
In many parts of New Zealand — particularly low-lying areas of Canterbury, Wellington, and the Bay of Plenty — liquefaction is a real risk. Signs include sand or silt ejected onto the ground surface, sunken paths or driveways, and tilting structures. If you see these signs, contact your council and an engineer. BRANZ has published research on earthquake performance of NZ homes that is worth reading.
Understanding the NZ Building Code Context
New Zealand homes are built to withstand earthquakes under the NZ Building Code, with structural timber framing typically following NZS 3604. However, older homes — particularly pre-1970s unreinforced masonry or pre-1935 construction — may not meet modern standards and are more vulnerable. If your home is older or has a brick or concrete block exterior, treat any damage as more serious until proven otherwise.
When to Call a Professional
Call a licensed building inspector or structural engineer if you find:
- Cracks wider than 5 mm, or cracks that are stepped or diagonal across masonry
- Any sign the building has shifted on its foundations
- A damaged or leaning chimney
- Doors or windows that no longer operate correctly
- Sagging or displaced roof structure
- Any evidence of liquefaction or ground subsidence
For electrical concerns — such as damaged wiring, tripped breakers that won't reset, or scorch marks — contact a registered electrician. Electrical work is restricted under the Electrical Workers Registration Board (EWRB) and must not be carried out by unlicensed persons.
For gas leaks or damaged gas fittings, this is restricted work under the PGDB. Turn off the gas at the meter and call a licensed gasfitter before using any gas appliance.
A qualified building inspector can provide a written report that satisfies your insurer and gives you confidence about the home's condition. You can find experienced local building inspectors on tradedirectory.co.nz.
Licensed Building Practitioner (LBP)
BCITO Qualified
