Most cladding doesn’t fail at once. It cracks, moves and lets in small amounts of water for years before you have to choose between another patch and starting over. If you’ve reached that point, plan for a managed project rather than a quick weekend fix.
How long different cladding types last
Weatherboard cladding uses overlapping horizontal boards to shed water down the wall. Each board laps over the one below, keeping the wall dry while the laps remain tight and the coating stays intact. Once the laps open or the coating breaks down, water gets in.
Timber weatherboard usually lasts 20 to 40 years when it’s repainted on schedule and kept clear of soil and splashback. We’ve pulled boards that still looked sound at 35 years because the owners recoated every eight to ten years and kept gutters clear. We’ve also removed boards that were soft at 18 years because the paint had been left to peel and garden beds were piled against the wall.
Fibre cement lasts much longer. A good installation can provide 50 or more years of service because the boards won’t rot and termites leave them alone. Vinyl sits in the middle at roughly 30 years. It doesn’t need paint, although it can warp in heat and crack with age.
Age alone doesn’t force replacement. Condition does. If your timber is approaching 30 years and paint won’t hold, it’s near the end. If your fibre cement is 25 years old, flat and tight, it may have decades left.
Paint hides a lot.
Boards that look tired on the surface
Walk the perimeter on a dry day and inspect the boards closely. Deep cracks running with the grain differ from hairline checking in the paint because they let water sit inside the board. That water freezes, swells and opens the crack wider each season.
Warped or wavy boards are another warning. Boards should sit flat with even shadow lines. Bellies or twists mean the board has moved, so the lap above it no longer sheds water cleanly. Press the suspect area with your thumb. Solid boards feel hard and don’t give, while rotted boards flex or feel spongy under pressure.
We call this the press test in our own checks. It takes seconds and tells you more than a photo.
Check board ends and joints carefully. Ends absorb water first, so rot often begins where two boards meet or where a board reaches the trim. Peeling paint that exposes bare timber in those areas isn’t merely cosmetic. Bare timber absorbs rain directly, and once the fibres soften, filler and spot paint won’t hold for long.
Two bad boards on one wall don’t require a full replacement. Widespread cracking and flex across several walls often do.
Signs water has got behind the boards
Surface damage is easy to see. Hidden moisture damage is what ruins walls.
Inside the house, check for yellow or brown stains on exterior walls and ceilings near the perimeter. A musty odour in rooms sharing a wall with failed cladding, especially after rain, is another warning. Feel for soft spots in gyprock around windows and near the floor. If a room smells damp and the wall feels soft, water has already passed through the cladding.
Outside, watch for blistered paint that keeps returning in the same place. One blister after a storm may be a one-off. The same blister after every repaint means moisture is pushing out from behind the board. Check beneath windowsills and where trim meets cladding. These joints rely on flashing to throw water clear, and old flashing often splits or pulls away.
Sarking, the moisture barrier behind the cladding, should catch small amounts of wind-driven water and drain them away. Old or torn sarking can’t do that job. Replacement is the right time to install new sarking, adding some work while protecting the frame for decades.
When interior stains and exterior blisters appear together, the cladding has stopped working as a weather barrier. Surface patches won’t fix the moisture behind it.
Pests and old sheet materials change the call
Timber weatherboards can look intact while insects eat them from within. Tap boards lightly with a screwdriver handle as you walk around. Solid timber gives a sharp knock, while damaged timber sounds hollow or dull. Probe gently around the base of walls and near timber stairs or decks. Termites travel up from the ground, so mud tracks on foundations or stumps indicate active movement.
Borers leave small exit holes and fine dust. Their damage is slower than termite damage, but it weakens boards and allows water through the holes. If more than a few boards sound hollow, arrange a pest inspection before deciding on repairs. Fitting new boards over an active colony in the frame won’t solve the problem.
Older sheet cladding presents a different risk. Homes built before 1985 may still contain asbestos cement sheet, often called fibro, beneath or beside later additions. You can’t always identify it by sight, so don’t cut or break suspect sheets to check. Arrange testing through a licensed assessor and have a licensed removalist handle confirmed material.
This isn’t rare. One in three Australian homes contains asbestos (Asbestos Safety and Eradication Agency). That figure affects both the budget and schedule. Asbestos removal requires containment and a compliance wait, so a one-day removal can add several days around it.
Why material choice sets the finishing time
New cladding involves more than appearance. The product you choose determines how many site days are needed for finishing.
Timber needs sealing on every side and multiple coats on the wall. Some fibre cement requires the same treatment. Factory priming helps, but full top coats are still needed on site, with dry weather and drying time between passes. This phase can take three to five days on a standard home and longer if rain interrupts.
Pre-finished boards avoid that phase. They arrive with a cured factory coating, allowing the crew to install them, touch up fixings and move on. There’s no wait for painters or the risk of losing a week to showers.
Homeowners who trade up to a weatherboard cladding brand name like Formplex regain the three to five days that finishing would otherwise occupy. On a tight building programme, that’s useful time as well as convenience.
James Hardie is the fibre cement benchmark many owners recognise, with a long track record when installed and coated to specification. Composite pre-finished systems use a different process. They cost more per square metre in some quotes, but shorten the programme because painting isn’t a separate trade visit. When comparing quotes, assess the material and finishing together. A cheaper board requiring five days of painting may cost more once labour and scaffold hire are included.
The choice also affects upkeep. Timber needs repainting to reach its full lifespan, while fibre cement requires recoating on its own cycle. Pre-finished composite is designed to hold its colour longer with less work, which matters if you don’t want to hire painters again in eight years.
How long a full replacement takes
A realistic replacement can run three to six weeks from the first call to the final touch-up. That period isn’t spent entirely on physical work. Decisions, approvals and drying time account for much of it.
Allow one to two weeks for quotes and material confirmation. Good builders need to inspect the site, measure, check corners and trims and confirm lead times for the selected boards. Don’t rush this stage. A quote based on guessed quantities can cause delays when extra boards have to be ordered.
If your area requires a building permit or council approval for a cladding change, allow one to four weeks. Rules vary by suburb and according to whether you’re changing the material or colour, so ask early. Your builder should explain what’s required after the first site visit. Starting without approval risks a stop-work order and further delays.
Where required, asbestos removal usually takes one to two days on site, plus clearance time. The crew establishes containment, removes sheets intact where possible and arranges disposal. Other wall work can’t continue in that zone until clearance is given, so surrounding trades must be planned accordingly.
Installation on a standard single-storey home usually takes one to two weeks. The crew removes old boards in sections, checks the frame, fits new sarking and fixes the replacement boards with the correct laps and flashings. Working in sections keeps the house weathertight if rain arrives. Exposing everything at once is faster only until it rains.
Finishing takes three to five days for products requiring on-site paint. This includes filling gaps, priming bare cuts and applying two top coats. Every step needs dry air. Pre-finished boards avoid most of this work and shorten the programme.
Clean-up and trim refitting happen alongside the final installation work. Downpipes and lights are replaced, and sealants are left to cure. The last board doesn’t mark completion. The wall is finished when water can’t enter around it.
What else stretches the schedule or shortens it
Two-storey homes take longer. Scaffolding requires setup and teardown, and crews work more slowly at height. It also reduces weather flexibility because large areas can’t be stripped quickly when the wind rises. Allow extra days for access even if the wall area looks similar on paper.
Rain affects more than painting. Crews can continue some tasks through light showers, but they won’t leave open walls exposed or coat wet timber. One wet week may delay finishing by several days. During a wet season, include a buffer and ask the builder how the removal will be staged to keep walls covered.
Trim and detail work also takes time. Window and door surrounds, corner boards and wall-to-eave junctions all require careful flashing. Replacing rotten trim at the same time is sensible, although it adds carpentry days. Rushed flashing is one of the quickest ways to create a leak in a new wall, so this work needs adequate time.
Adding sarking and insulation extends the job slightly. With the wall open, it’s the best opportunity to upgrade both. New sarking improves water management, while new wall insulation increases comfort and can improve energy performance by raising the wall’s R-value. The extra material and labour cost money, but there won’t be a cheaper opportunity.
Site access matters more than many owners expect. Stripping and cutting create noise and dust. Keep the house perimeter clear so crews can move boards and set trestles without relocating stored items each morning. Discuss downpipes and exterior lights with the builder, as they usually need removal and refitting.
Air-conditioner lines running across walls also need attention. Have a technician move or disconnect them before cladding work begins so the crew isn’t waiting for another trade mid-week. Small delays like these add up to lost days.
Resale value often influences the final decision. Updated cladding quickly improves kerb appeal because it’s the first thing buyers see. Tired boards can make buyers assume the worst about the structure behind them. Tight, straight boards and clean trims suggest a well-maintained house, which comes through in photos and inspections.
Replacement feels substantial because it affects every side of the house. It runs more smoothly when you recognise the early signs, choose a material suited to your timeline and give each stage the time it needs.
