A fairly common problem with terracotta roof tiles in Melbourne is called fretting.
Fretting on a terracotta roof tile has various causes, and salt is one common culprit. However, it is quite a difficult task to pinpoint the exact cause of the fretting. Some particular brands and production runs of roof tiles seem to suffer a lot more than others. Some very old terracotta roof tiles do not fret, yet younger tiles do. Some terracotta roofs near the sea suffer bad fretting, while others fare quite well.
And the problem is that most of the fretting problems occur under the lap of the roof tiles, so it is not immediately obvious where the problem tiles are. Each tile has to be inspected by lifting up the neighbouring tiles.
For roofs with no sarking, it is usually easier to inspect for fretting from the roof cavity, because the terracotta colour powder of the fault will fall onto the surface of the ceiling and the roof battens.
This layer of dust is easy to spot. With sarked roofs, it is a bit more difficult.
What Causes Fretting in Terracotta Tiles?
Fretting is usually the result of a combination of factors rather than a single issue. The most common include:
- Salt deposits are carried by wind or water, especially on roofs near the bay or exposed to sea air.
- Manufacturing variations, where some production runs are far more prone to deterioration than others.
- Moisture and Melbourne’s climate, with frequent rain and temperature shifts, are accelerating wear.
- Roof location and exposure, with roofs facing prevailing winds or storms deteriorating more quickly.
How to Identify Fretting On Your Roof
Signs of fretting include:
- A fine red or terracotta-coloured dust appears in the roof cavity, on battens, or on the ceiling.
- Tiles that crumble or weaken when inspected.
- Patches of deterioration that may spread across sections of the roof.
Because most fretting occurs beneath the lap of tiles, it is not always visible from the outside, and we always recommend careful inspection.
Why Fretting is a Serious Problem
Fretting is often compared to cancer for roof tiles, not the nicest description, but once it starts, it can spread and worsen over time. Left untreated, roof tile fretting can lead to:
- Leaks and water ingress
- Damage to battens and timbers from falling dust and moisture
- Loss of strength and safety in the roof structure
- The need for frequent, costly repairs
Repairing and Replacing Fretting Tiles
A short-term solution is to replace tiles that are badly fretting. However, this only works if the problem is confined to a small area.
If fretting is widespread, patching is not practical. In these cases, you should consider a tile roof replacement or full roof restoration to provide a long-term solution. Metropolitan Roof Repairs specialises in terracotta tile roof repairs, tile roof restoration and complete roof replacement. We repair roofs across Melbourne, including heritage buildings where preservation and expert care are essential.
Get a Free Inspection
If you’ve noticed powdery residue, weak tiles, or suspect fretting may be affecting your roof, now is the time to act. Metropolitan Roof Repairs provides free inspections and quotes throughout Melbourne and can give you clear advice on whether tile roof repairs, restoration, or a new roof is the best option.
Call today on 03 8678 0398 or request your free quote online.
