Yes, as a homeowner you can identify many of the early warning signs that your cladding is cracking or failing — and catching problems early can save you thousands of dollars in repairs. That said, some defects are hidden behind the surface, so knowing the limits of a visual check is just as important as knowing what to look for.
Why Cladding Condition Matters
Your home's cladding is its first line of defence against the weather. When it fails, water can penetrate the wall system, leading to weathertightness issues, rotting framing, mould, and structural damage. In New Zealand, weathertight failures became a major issue in the late 1990s and 2000s — the so-called "leaky home" era — and the consequences for homeowners were severe. The MBIE Building Performance website has useful background on weathertightness and the NZ Building Code requirements (particularly Clause E2 – External Moisture).
Common Types of Cladding in NZ Homes
Before you inspect, it helps to know what type of cladding you have, as failure signs differ:
- Fibre cement (e.g. James Hardie products like Harditex or Linea)
- Monolithic plaster systems (stucco or texture-coated)
- Weatherboard (timber or fibre cement)
- Brick veneer
- Metal cladding (Colorsteel or similar)
Each system has its own vulnerabilities. Monolithic plaster cladding, in particular, has been associated with weathertightness failures in NZ. James Hardie provides product-specific guidance for their cladding systems.
What to Look For: Visual Inspection Checklist
Walk around the outside of your home on a dry day and check the following:
Cracks and Gaps
- Hairline cracks in plaster or fibre cement — these can allow water ingress even if they look minor
- Larger structural cracks, especially diagonal cracks near window and door corners
- Gaps at junctions — where cladding meets window joinery, soffits, decks, or rooflines
- Cracking or separation at control joints and butt joins
Paint and Surface Condition
- Bubbling, peeling, or flaking paint — often a sign of moisture behind the cladding
- Staining or tide marks — rust streaks, dark patches, or efflorescence (white salt deposits on masonry or plaster)
- Chalking or fading beyond normal weathering
Sealants and Flashings
- Cracked, shrunken, or missing sealant around windows, doors, penetrations, and joints
- Damaged or incorrectly installed flashings — these are critical to keeping water out
- Check that window sills slope away from the building to shed water
Soft Spots and Damage
- Gently press on cladding surfaces — soft or spongy areas in fibre cement or plaster can indicate moisture damage or rot behind
- Look for impact damage, holes, or areas where cladding has shifted or bowed
Ground and Drainage
- Check that ground clearance is adequate — cladding should generally be at least 150 mm above finished ground level (check your cladding manufacturer's requirements)
- Look for soil or mulch piled against cladding, which traps moisture
- Ensure downpipes and gutters are directing water away from the building
Inside the Home: Interior Warning Signs
Don't forget to check inside too:
- Damp patches or staining on interior walls, especially below windows or near exterior walls
- Mould or mildew on walls or in wall cavities (check behind furniture pushed against exterior walls)
- Musty smells in rooms or subfloor spaces
- Swelling or warping of interior linings near exterior walls
For guidance on healthy indoor environments, Tenancy Services covers moisture and mould requirements under the Healthy Homes Standards.
Using a Moisture Meter
A moisture meter (available from Bunnings or Mitre 10) can help you check moisture levels in timber or cladding surfaces. Readings consistently above around 18–20% in timber may indicate a problem (check the meter manufacturer's guidance and consult a professional for interpretation), though meters vary in accuracy and surface readings don't always reflect what's happening deeper in the wall. Use this as a guide, not a definitive test.
Limitations of a DIY Inspection
A visual check has real limits. Many serious weathertightness defects are hidden within the wall system — behind cladding, in the cavity, or in the framing. Problems at high-risk areas such as parapets, balconies, low-slope roofs, and complex junctions often can't be assessed from the ground. BRANZ research has consistently shown that early professional assessment leads to significantly lower repair costs.
When to Call a Professional
Call a licensed building inspector or building surveyor if you:
- Find any of the warning signs listed above
- Are buying or selling a home
- Have a monolithic plaster-clad home built between approximately 1990 and 2005
- Notice recurring damp or mould issues inside
- Want a moisture investigation using specialist tools (thermal imaging, invasive probing)
A qualified inspector can carry out a thorough weathertightness assessment and advise whether repairs, recladding, or a building consent is required. Some cladding repair work may require a building consent — always check with your local council before starting significant work. The Licensed Building Practitioners register can help you find appropriately licensed professionals.
You can also find experienced local building inspectors on tradedirectory.co.nz to get a professional assessment.
Licensed Building Practitioner (LBP)
BCITO Qualified
