Weatherboard is the most common cladding type on older New Zealand homes. Rimu, macrocarpa, and pine weatherboards were standard on houses built from the 1900s through to the 1970s, and most are still standing — provided they've been kept painted and maintained.
A well-maintained weatherboard house can last indefinitely. An unmaintained one deteriorates fast.
How Weatherboard Works — and Why It Fails
Weatherboard relies entirely on paint to keep moisture out. The timber itself is not waterproof; the paint is the weatherproofing layer. When the paint fails — through cracking, peeling, chalking, or missing coverage — water gets into the timber grain and rot begins.
The most vulnerable spots:
- Bottom boards — closest to the ground, exposed to splash-back, and where water pools in the cavity
- Window sills — horizontal surfaces that hold water; sill flashings fail over time
- Around fixings — nails and screws can rust and crack the paint around them
- Under eaves overhangs — where two boards meet or where the overhangs is insufficient
- South-facing elevations — least sun, most moisture, longest drying time
- Coastal areas — salt spray accelerates paint degradation significantly
How to Inspect Your Weatherboard
Walk around your house every year and check:
- Look for paint failure — chalking (paint rubs off on your finger), peeling, blistering, bare timber showing at cut ends or edges
- Check caulking joints — gaps at window frames, corners, and trim let water in
- Probe for rot — push a penknife or screwdriver firmly into any suspicious areas. Firm timber is healthy; spongy or crumbly timber is rotted
- Look at the bottom course — boards within 150mm of ground level take the most punishment
- Check the fascia and bargeboards — often painted at the same time as weatherboards and fail similarly
Repainting Schedule
| Condition | Repaint interval |
|---|---|
| Quality paint, sheltered/inland location | 10–12 years |
| Quality paint, exposed or coastal location | 6–8 years |
| Budget paint or poor original preparation | 4–6 years |
| Already peeling, bare timber showing | Do it now |
Don't wait until the paint is peeling to repaint — by the time it's peeling, water has already penetrated and timber damage follows quickly. Repaint while the surface is still sound.
Rot Repair Costs
| Scope | Typical Cost |
|---|---|
| Single board section replacement (1–2 boards) | $300–$800 |
| Window sill rot repair and resealing | $400–$1,200 |
| Corner rot repair (one corner) | $600–$1,500 |
| Extensive rot (multiple sections, multiple locations) | $2,000–$8,000+ |
| Full reclad (extreme deterioration) | $60,000–$150,000+ |
Rot caught early — a single soft board or a failed sill — is a minor repair. Rot left for years can spread through framing and require a full reclad. Early intervention always costs less.
Full Repaint Costs
| House size | Typical repaint cost |
|---|---|
| Small 2–3 bedroom bungalow (weatherboard in good condition) | $8,000–$12,000 |
| Standard 3–4 bedroom villa | $12,000–$18,000 |
| Large 4+ bedroom villa or two-storey | $18,000–$30,000+ |
| Same houses with extensive rot repair and prep | Add $3,000–$15,000 |
What drives the price up: - More than 10% of boards need replacing - Heavy chalking or peeling requiring extensive scraping and sanding - Lead paint present (requires lead-safe work practices) - Difficult access (high gables, scaffold required) - Cedar or other premium timber specified as replacement
Asbestos and Lead Paint Caution
If your weatherboard home was built before 1980:
- Lead paint is almost certainly present. Do not sand or scrape dry — use wet methods or hire a painter trained in lead-safe practices
- Asbestos is less common in weatherboards themselves but may be present in soffits, fascias, window surrounds, and any fibrous cement sheets used as patch repairs. Get any suspect materials tested before sanding, cutting or removing
A reputable painter will ask about and assess for these materials. If yours doesn't mention them, ask.
Choosing a Painter
Get at least three quotes. Ask each painter:
- How will you prepare the surface? (The answer should include: pressure washing, scraping, sanding, filling nail holes and cracks, priming bare timber)
- What paint system will you use, and what manufacturer's warranty applies?
- How do you handle lead paint?
- What warranty do you offer on the work?
Cheap quotes usually mean inadequate preparation — and a repaint that fails in 3–4 years instead of 10.