Most homeowners ask the question after the second or third leak, which is late — by then the evidence is usually in the structure rather than the covering.
Repair when…
- The fault is identifiable and local — one cracked tile, one lifted lap
- The surrounding covering has years of life and matching sheets are available
- Purlins are dry, straight and free of rust at the fixing points
- The damage traces to an event, such as a storm or a new solar mounting
Replace when…
- Leaks keep appearing in new places each rainy season
- Fixings no longer bite — sheets move or rattle even after re-screwing
- Cut-edge rust is spreading away from the eaves and overlaps
- The structure itself needs opening up, so the covering has to come off anyway
- A year of chasing repairs has cost a meaningful share of re-roofing
The honest middle path
Open one representative section before deciding. A single square metre above the worst ceiling tells you whether the purlins are sound — and a re-cover over rotten timber fails faster than the roof you removed. Read more on the roof repair page.