# Metal roof repairs in Perth

URL: https://perthroofquotes.com/metal-roof-repairs-perth/
Updated: 2026-10-17

> Metal roof repairs fix the parts of a steel roof that let water in or allow sheets to move: loose or rusted screws, perished sealing washers, lifted sheets, failed flashings and corroded areas. Repairs suit a roof whose sheets are mostly sound. Where rust has perforated sheets or spread widely, replacing those sheets, or the whole roof, is usually the more durable option.

Metal roofs rarely fail across a whole sheet at once. Problems start at the details: screws, laps where sheets overlap, cut edges, flashings and sections the rain does not wash clean. A good repair finds which is at fault and fixes it with materials that suit the existing roof.

In Perth you will see three broad kinds of metal roof. Pre-painted steel such as COLORBOND steel is the most common on newer homes and reroofs. Unpainted ZINCALUME steel has a silver-grey finish. Older homes, especially character cottages in the inner suburbs, may still have galvanised steel, often called "tin" or "corrugated iron". The repair approach differs for each.

## Which type of metal roof do you have?

| Roof type | What it is | Repair considerations |
|---|---|---|
| Galvanised steel ("tin") | Steel with a zinc coating, common on older homes | The zinc wears away with age and rust follows; new parts must be compatible with old sheets |
| ZINCALUME steel | Unpainted steel with a metallic alloy coating of aluminium, zinc and magnesium | Lead and copper must not touch it or drain onto it |
| Pre-painted steel (COLORBOND steel) | Metallic-coated steel painted on the factory coating line | Replacement sheets may not match a faded roof; paint condition affects repair options |

BlueScope's compatibility tables also say water should not drain from zinc-coated (galvanised) steel onto ZINCALUME or pre-painted steel, so partly replacing an older roof needs thought about which way the water runs. Our guide to [Perth roof types](https://perthroofquotes.com/guides/perth-roof-types/) explains how to tell the materials apart.


**Not sure it is metal?** Some older Perth homes have corrugated asbestos cement roofs, which have deep, wide corrugations and a grey cement look. Do not drill, cut, walk on or pressure clean a suspected asbestos roof. See [asbestos roofs in Perth](https://perthroofquotes.com/guides/asbestos-roofs-in-perth/).

## Signs your metal roof may need repairs

Most can be seen from the ground or an upstairs window.


- Rust spots or streaks around screw heads, at sheet laps or near the gutter line.
- Screws that have backed out, are missing or sit at an angle.
- Sheet edges lifting, rattling or banging in the wind.
- Paint that is flaking or chalky, with brown rust showing through.
- Ridge capping or barge capping (the trim along a gable edge) that is loose or bent.
- Old silicone patches, especially around screws and flashings.

## Screws, washers and fixings

Each roofing screw holds the sheet to a batten and seals the hole with a rubber washer under its head. Lysaght's re-roofing guidance calls for screws with EPDM rubber sealing washers that comply with AS 3566 Class 3 or higher. Over years of sun and heat, washers can harden and crack, and screws can loosen as sheets move, rust if the coating is damaged, or be overtightened so the washer splits.

A repair usually means replacing failed screws rather than tightening them, and using a larger screw where a hole has worn oversized. Ask what screw class and finish will be used, and whether it matches the roof colour.

## Lifted sheets and wind

Sheets lift when fixings fail or battens loosen. A lifted edge lets in wind-driven rain and gives a strong wind something to grab. Refixing usually means new screws into sound battens; loose or decayed battens make it a bigger job. If a sheet is flapping in a storm and you cannot make it safe, call the SES on 132 500 and see [storm damage roof repairs](https://perthroofquotes.com/storm-damage-roof-repairs-perth/).

## Rust and corrosion: what can be repaired?

The answer depends on how far the rust has gone.

- **Surface rust** on a sheet that is still solid can often be cleaned, treated and painted with a compatible system.
- **Rust at laps and cut edges** can sometimes be treated, but it often means water has been sitting where it should not.
- **Perforation**, where rust has eaten through, needs the affected sheet replaced. Paint or sealant over a hole is a temporary measure.

Metal filings left behind after drilling and cutting are another source of rust spots. Lysaght advises removing leftover fasteners, rivet stems and metal scraps immediately to prevent rust stains, so ask how swarf (the fine metal particles from cutting) will be cleaned off. The guide to [rusty roofs and gutters](https://perthroofquotes.com/guides/rusty-roofs-and-gutters/) covers treatment options.

### Coastal salt

Salt air corrodes metal roofing, fixings and flashings faster near breaking surf, and areas the rain does not wash, such as under eaves and at overlaps, collect salt and often corrode first. BlueScope grades its products by distance from the surf, with marine-grade products recommended closest to the coast. Tell the contractor if you are near the ocean, and ask which product and warranty suit your exact site. See [coastal roofs and salt corrosion](https://perthroofquotes.com/guides/coastal-roofs-and-salt-corrosion/).

*Image: A coastal home with a light steel roof. Salt-laden air near the surf shortens the life of exposed metal, fixings and flashings.*
### Dissimilar metals

Some metals damage coated steel when they touch it or when water runs off them onto it. Lysaght's compatibility guidance lists lead, copper and most stainless steel as not compatible with ZINCALUME and COLORBOND steel. In practice this rules out old lead flashings draining onto a new steel roof, copper hot water overflow pipes discharging onto sheets, and mixed fixings. Ask the contractor to confirm that every new screw, rivet, flashing and gutter is compatible with your roof. [Roof flashing repairs](https://perthroofquotes.com/roof-flashing-repairs-perth/) covers flashing materials.

## Why does a metal roof creak and bang?

Steel expands as it heats and contracts as it cools, so on a hot Perth afternoon, or when cloud passes over, sheets move against battens and fixings and can tick or creak. That is normal for many metal roofs. Loud banging in wind, or a new noise, can mean loose fixings or a lifting sheet and is worth having checked.

## Are sealant-only patches a proper repair?

Rarely. Lysaght advises using only neutral-cure silicone made for metallic-coated and pre-painted steel, because some silicones give off aggressive by-products while curing. It also notes that most sealants are not adhesive, so the steel still needs proper fixing. Sealant has a role in sealing laps and flashings as part of a correct detail, but a smear over a hole, a rusted lap or a lifted flashing is a stopgap, and old patches can hide how far corrosion has spread.

## When do sheets need replacing?

Replacement is usually the better option when sheets are rusted through, when corrosion has spread along many laps, or when an old galvanised roof has lost its coating over large areas. A single sheet can often be replaced on its own, usually full length from ridge to gutter. A pre-painted replacement sheet may look brighter than the faded sheets beside it.

When patches and replaced sheets start to add up, compare the options in our [repair, restoration or replacement guide](https://perthroofquotes.com/repair-or-restoration/) and read about [roof replacement](https://perthroofquotes.com/roof-replacement-perth/).

## What should a metal roof repair quote clarify?

- **The defects found**, with photos: which screws, sheets, laps or flashings.
- **Repair method**: replace screws or sheets, refit flashings, or treat rust, and the products used.
- **Material compatibility** of every new part with the existing roof.
- **What is not included**, such as gutters or rusted areas noted for later.

## What is usually included, and what is not?

| Usually included | Often extra or excluded | Worth asking about |
|---|---|---|
| Replacing failed screws and washers | Replacing battens | The screw class and colour |
| Refixing lifted sheets | Full sheet replacement | Whether sheets are full length |
| Treating minor surface rust | Coating the whole roof | The rust treatment product |
| Removing swarf and offcuts | Gutter and fascia repairs | How swarf will be cleared |

## What affects the price of metal roof repairs?

- **Extent of the problem.** A handful of screws is a different job from many corroded laps.
- **Sheet replacement.** Sheet length and profile, colour, and whether the profile is still made.
- **Height, pitch and access.** Two-storey homes and steep roofs need more equipment.
- **Location.** Coastal sites may need marine-grade products.

See [roof repair costs in Perth](https://perthroofquotes.com/roof-repair-cost-perth/) for how repair quotes are usually set out.

[Request a roof quote](https://perthroofquotes.com/quote/)
## Questions to ask the contractor


- Which defects are causing the leak or movement, and can you show me photos?
- Will you replace screws rather than tighten them, and with what class of screw?
- Are all new materials compatible with my existing roof?
- How will metal filings and offcuts be removed from the roof and gutters?
- If I am near the coast, which product grade do you recommend and why?

## Frequently asked questions

### Should loose roof screws be tightened or replaced?
Usually replaced. A screw that has worked loose has often worn its hole or damaged its sealing washer, so tightening it may not seal. A replacement screw, sometimes a larger one, gives a fresh washer and a firm hold.

### Can a rusty metal roof be painted instead of replaced?
If the rust is on the surface and the steel is still sound, cleaning, treating and painting can be an option. Paint does not repair sheets that have rusted through, so those sections need replacing first.

### Can one damaged roof sheet be replaced on its own?
Often, yes. A single sheet is usually replaced full length from ridge to gutter, and the contractor should check that the new sheet's profile, coating and colour suit the sheets around it.

### Is a tin roof the same as a Colorbond roof?
Not quite. "Tin" is a common name for older galvanised steel roofs. COLORBOND steel is a pre-painted steel with a metallic coating under the paint, and it needs compatible fixings and flashings.

### Will new roof sheets match the colour of my faded roof?
New pre-painted sheets are usually brighter than sheets that have faded in the sun, even in the same named colour. Ask the contractor where the new sheets will go and how noticeable the difference is likely to be.