Repair Systems — 04
Valley flashing systems — aluminium
Technical product reference for aluminium valley flashing systems used in pitched tiled roof leak repair. Covers product classification, material options, fixing requirements, lapping, and brand comparisons for Australian residential and Class 2 strata applications under AS 1562.1.
What are aluminium valley flashings?
Aluminium valley flashings are roll-formed or custom-formed metal sheets installed in the valley of a pitched tiled roof to collect and direct rainwater running off both sides of the valley down to the gutter. The valley is one of the highest-risk water entry points on a pitched tiled roof — an undersized, incorrectly lapped, or failed valley iron is one of the most common causes of roof leaks on residential and Class 2 strata buildings in Australia.
Product Reference
3 products — 3 brands — aluminium valley flashing systems only — scroll to view all
Capral Aluminium Valley Iron
Mill-finish roll-formed aluminium valley iron — AS 1562.1
System Description
Capral Aluminium Valley Iron is a mill-finish aluminium valley flashing roll-formed from Capral 5000-series aluminium alloy. Available in standard valley widths of 150mm, 200mm, and 250mm in standard lengths, the product is suitable for standard tile valley replacement on all common Australian roof types including terracotta and concrete tiled roofs. Aluminium valley iron is lighter than Colorbond steel and will not rust, making it a practical alternative where corrosion resistance is a priority and colour matching is not critical. Mill-finish aluminium is uncoated and will not match the colour of Colorbond or terracotta tiles without painting — where colour match is required, the cured aluminium can be painted with an appropriate metal primer and compatible roof tile paint. Confirm compatibility with the tile manufacturer's valley width requirements and minimum lap at gutter outlets from the current Capral technical documentation and the tile manufacturer's fixing guide. Valley iron must be fixed to roof battens in accordance with AS 1562.1 and the tile manufacturer's installation requirements.
Technical Properties
- Roll-formed from Capral 5000-series aluminium alloy — corrosion-resistant — will not rust in exposed external roofing environments
- Mill-finish (uncoated) — lighter than Colorbond steel valley iron — standard widths: 150mm, 200mm, 250mm
- Suitable for standard tile valley replacement on terracotta and concrete tiled roofs — all common Australian roof types
Limitations
- Mill-finish (uncoated) — will not match the colour of Colorbond or terracotta tiles without painting — colour match requires metal primer and compatible roof tile paint
- Not a factory pre-painted product — where an aesthetically matched factory finish is required, specify Colorbond valley iron instead
- Confirm valley width is compatible with the tile profile and tile manufacturer's fixing requirements — do not specify a width that is narrower than the minimum required by the tile manufacturer
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Metalcorp Aluminium Valley Flashing
Roll-formed aluminium valley flashing — mill-finish and pre-painted
System Description
Metalcorp Aluminium Valley Flashing is an aluminium valley flashing formed from Metalcorp aluminium sheet, available in both mill-finish and pre-painted finishes. The availability of a pre-painted finish makes Metalcorp aluminium valley flashing a practical option where a colour-matched valley flashing is required without the cost or lead time of custom fabrication. Pre-painted options are available in a range of standard colours — confirm available colours from Metalcorp trade supply before specifying for colour match applications. Suitable for terracotta and concrete tile valley replacement. As with all aluminium valley flashings, fixing to roof battens must be in accordance with AS 1562.1 and the tile manufacturer's valley installation requirements. Confirm standard widths, available colours, and lead times from Metalcorp trade supply before ordering.
Technical Properties
- Aluminium valley flashing formed from Metalcorp aluminium sheet — available in mill-finish and pre-painted finishes
- Pre-painted finish available — eliminates the need for on-site painting for colour match applications — confirm available colour range from Metalcorp
- Suitable for terracotta and concrete tile valley replacement — standard valley widths — confirm from Metalcorp trade supply
Limitations
- Confirm pre-painted colour range from Metalcorp trade supply before specifying for colour match applications — limited colour range compared to Colorbond
- Pre-painted finish may not match existing Colorbond or terracotta tile colours exactly — confirm colour match before installing
- Confirm valley width is compatible with the tile profile and tile manufacturer's fixing requirements — confirm minimum lap at gutter outlet from AS 1562.1
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Custom Roll-Formed Aluminium Valley
Custom-formed heavy-gauge aluminium valley flashing — non-standard profile
System Description
Custom Roll-Formed Aluminium Valley is a custom-formed aluminium valley iron fabricated from 3mm aluminium alloy sheet by a specialist roofing metal fabricator. This option is used where the valley width, profile, or depth required on the specific project does not match any standard off-the-shelf aluminium valley iron product. Custom fabrication allows the valley profile to be matched to a specific tile profile, to a heritage building requirement, or to a non-standard roof geometry. Specify profile, width, and length with the fabricator — a profile drawing or site template is typically required for accurate fabrication. Lead times for custom fabrication are longer than for standard products — allow adequate lead time in the programme. Lysaght and other roofing metal fabricators can provide custom fabrication from aluminium sheet — confirm capability and lead time with the selected fabricator before specifying. Confirm that the fabricated valley complies with AS 1562.1 valley flashing requirements for the specific roof type, tile manufacturer fixing requirements, and minimum lap at the gutter outlet.
Technical Properties
- Custom-formed from 3mm aluminium alloy sheet by specialist roofing metal fabricator — suited to non-standard valley width, profile, or depth requirements
- Heavy-gauge aluminium — greater rigidity than standard roll-formed valley iron — suited to wide valleys and high-load applications
- Fabricated to profile drawing or site template — allows exact match to tile profile, heritage requirement, or non-standard roof geometry
Limitations
- Longer lead time than standard off-the-shelf valley iron — confirm fabrication and delivery lead time with fabricator before specifying for time-critical programmes
- Higher cost than standard valley iron — custom fabrication involves additional labour and material cost — obtain a quotation from fabricator before specifying
- Profile drawing or site template required for accurate fabrication — do not order without a confirmed profile specification
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of aluminium valley flashing systems. Confirm all product selections against the current manufacturer TDS before specifying.
| Product | Brand | Material | Finish | Width options | Corrosion resistance | Colour match | Fabrication |
|---|---|---|---|---|---|---|---|
| Capral Valley Iron | Capral | 5000-series aluminium alloy | Mill-finish (uncoated) | 150mm, 200mm, 250mm standard | Excellent — will not rust | Paint on site — not factory colour | Standard roll-formed |
| Metalcorp Valley Flashing | Metalcorp | Aluminium sheet | Mill-finish or pre-painted | Standard — confirm with Metalcorp | Excellent — will not rust | Pre-painted options available | Roll-formed |
| Custom Aluminium Valley | Custom fabricator | 3mm aluminium alloy sheet | Mill-finish (painted on order) | Any — custom to specification | Excellent — will not rust | Paint on site or order painted | Custom — profile and width to drawing |
Do not confuse aluminium valley iron with:
- Colorbond valley iron (BlueScope/Lysaght/Stramit) — factory pre-painted Colorbond steel — different material, factory colour coating system, Zincalume or Colorbond steel substrate — listed on the Colorbond valley flashing page
- Lead valley flashing — traditional soft lead sheet valley iron used in heritage and premium applications — different material, heavier, different working characteristics — listed on the copper valley page context
- Zincalume valley iron (unpainted) — Zincalume steel without Colorbond colour coating — do not substitute for painted Colorbond or aluminium without confirming compatibility with tile type
- Copper valley flashing — architectural copper sheet valley iron — different material, develops natural patina — listed on the copper valley flashing page
Disclaimer
Valley width, profile and lap must comply with tile manufacturer requirements. Confirm with roofing contractor. This page provides general technical information only. Final product selection must be confirmed against the current manufacturer technical data sheet, project specification, tile type, roof pitch, and AS 1562.1 requirements where applicable. Do not rely on this reference as a substitute for professional roofing or building consultant advice.