Metal Flashings
Correctly specified and installed flashings are the single most important factor in a watertight metal roof or wall system. Steel Source Australia supplies the complete range — ridge, barge, apron, valley, fascia, wall and penetration flashings — in COLORBOND®, Zincalume®, galvanised and 316 stainless steel, all fabricated to comply with AS 1562.1:2018 and NCC 2022 weatherproofing requirements.
AS 1562.1:2018
Design and installation of sheet roof and wall cladding (metal) — the primary Australian Standard governing flashing design, minimum leg lengths, lap requirements and fixing centres.
NCC 2022 Compliance
All standard flashings are dimensioned to meet NCC 2022 Volume One and Volume Two weatherproofing requirements for residential and commercial construction.
BlueScope Warranty
COLORBOND® and Zincalume® flashings are manufactured from genuine BlueScope steel. Using matching material and colour is required to maintain the BlueScope product warranty.
Material Certification
All steel supplied with mill test certificates (MTC) confirming compliance with AS 1397:2021 for COLORBOND® and Zincalume®, and AS/NZS 1554.6 for 316 stainless steel.
Material Selection Guide
Selecting the correct flashing material for your corrosivity environment is critical for long-term performance. The table below summarises the four materials Steel Source Australia stocks, their applicable Australian Standard, and the environments they are — and are not — suited to.
COLORBOND®
0.42 BMT / 0.48 BMT — AS 1397:2021 G550 AZ150
Use for
Residential and commercial roofing and walling. Colour-matched to roof sheeting. BlueScope warranty requires matching colour and grade.
Avoid
Direct contact with copper, lead or treated timber (CCA/ACQ). Use isolation tape or EPDM gaskets.
Zincalume®
0.42 BMT / 0.48 BMT — AS 1397:2021 G550 AZ150
Use for
Concealed flashings, valleys, penetrations and any application where colour match is not required. Superior corrosion resistance to standard galvanised.
Avoid
Direct contact with copper or lead. Not suitable for food-grade or pharmaceutical environments.
Galvanised G300
0.42 BMT / 0.48 BMT — AS 1397:2021 G300 Z275
Use for
Agricultural, industrial and rural applications. Lower cost than COLORBOND® or Zincalume®. Suitable for inland, low-corrosivity environments (C1–C2 per AS/NZS 2312.2).
Avoid
Coastal environments within 1km of breaking surf (C4–C5 classification). Contact with dissimilar metals.
316 Stainless
0.40 BMT / 0.50 BMT — AS/NZS 1554.6 — Grade 316L
Use for
Severe marine environments (within 100m of breaking surf), food processing, pharmaceutical and swimming pool surrounds. Maximum service life.
Avoid
Contact with carbon steel fixings — use A4-grade (316) stainless screws and rivets only.
Corrosivity classification: Material selection must be based on the corrosivity category of the project site as defined in AS/NZS 2312.2:2014 — Guide to the protection of structural steel against atmospheric corrosion by the use of protective coatings. Coastal sites within 1km of breaking surf are typically classified C4 or C5 and require Zincalume® or 316 stainless as a minimum. If in doubt, contact our technical team before ordering.
COLORBOND® Colour Selection
Select a colour below to filter the flashing catalogue to show only that colour's SKUs. All COLORBOND® flashings are manufactured from genuine BlueScope steel — colour must match your roof sheeting to maintain the BlueScope warranty.
Colour swatches are approximate visual representations only. Actual COLORBOND® colours may vary from screen display. Always request a physical colour sample from Steel Source Australia before ordering. Colours subject to availability — contact us to confirm stock.
Flashing Catalogue
78 SKUs across 8 categories. Expand each section to view products and add to enquiry.
Critical Installation Requirements
The following requirements apply to all metal flashing installations under AS 1562.1:2018 and NCC 2022. These are minimum standards — your engineer or certifier may specify more stringent requirements for your project.
Minimum Leg Lengths
All flashings must have a minimum leg length of 100mm in contact with the roof or wall surface (AS 1562.1:2018 Cl. 4.2.3). Ridge and barge capping: 150mm minimum. Valley flashings: 100mm under sheeting each side.
Lap Joints
All lap joints between flashing lengths must be a minimum of 150mm in the direction of water flow. The upper length must always lap over the lower length. Apply neutral-cure silicone sealant to all lap joints.
Fixing Requirements
Flashings must be fixed at maximum 600mm centres using Class 3 hex-head screws for COLORBOND® and Zincalume®, or A4-grade stainless screws for 316 stainless flashings. Never use plain steel or zinc-plated screws.
Sealant Specification
Use only neutral-cure (oxime) silicone sealant on COLORBOND® and Zincalume® flashings. Acetoxy-cure (acetic acid) silicone releases acetic acid during cure, which attacks the zinc-aluminium coating and voids the BlueScope warranty.
Dissimilar Metals
Never allow direct contact between COLORBOND® or Zincalume® flashings and copper, lead or uncoated carbon steel. Use EPDM isolation tape or neoprene gaskets at all contact points. Galvanic corrosion will occur within 12–24 months in wet conditions.
Treated Timber
CCA and ACQ treated timber contains copper compounds that are highly corrosive to zinc-coated steel. Always use a physical barrier (EPDM tape or polyethylene strip) between treated timber and COLORBOND® or Zincalume® flashings.
Need a non-standard profile?
Steel Source Australia operates in-house brake-press fabrication for custom flashings. If your project requires a non-standard leg length, a complex multi-bend profile, or a specific material grade, our fabrication team can produce it. Provide a dimensioned sketch or DXF file and we will return a quote within one business day.
- Any profile — brake-pressed to your drawing
- COLORBOND®, Zincalume®, galvanised or 316 stainless
- Quote within one business day
- Minimum order quantities apply — contact us for details