Repair Systems — 04
Colorbond steel rainwater head systems for box gutters
Rainwater heads (also called rain heads or conductor heads) are fabricated sheet metal boxes that collect box gutter discharge and transition the flow into downpipes, reducing turbulence and debris blockage risk. Colorbond steel rainwater heads are the most common specification on Australian strata buildings, available custom-fabricated or as proprietary units in all standard Colorbond colours.
What are Colorbond steel rainwater heads for box gutters?
Rainwater heads — also called rain heads or conductor heads — are fabricated sheet metal boxes mounted at the outlet of a box gutter that collect the gutter discharge and transition the flow from the wide gutter section into a downpipe. They reduce turbulence at the gutter-to-downpipe transition, slow the water velocity to reduce the risk of debris blockage in the downpipe, and provide a visible overflow indicator when the drainage system is at capacity. On Australian Class 2 strata buildings, Colorbond steel is the most common specification for rainwater heads due to its durability, wide colour range, and availability through national fabricators.
Product Reference
3 products — 3 brands — Colorbond steel rainwater heads for box gutters — scroll to view all
Lysaght Custom Colorbond Rainwater Head
Custom-fabricated Colorbond steel rainwater head — Lysaght
System Description
Lysaght Custom Colorbond Rainwater Heads are fabricated from BlueScope Colorbond Ultra steel at Lysaght branch workshops to project specification. Custom widths from 200mm to 600mm and depths from 100mm to 250mm are available. All standard Colorbond colours can be matched to adjacent gutter lining and downpipe systems. Strap outlet collars are factory-formed to DN90 or DN100 for connection to round downpipes. Factory-folded seams provide a clean, weathertight joint without site fabrication risk. Lysaght's national branch network means supply is available in all major Australian states and territories — confirm lead time and nearest branch capability before programming installation. Specify the required width, depth, inlet opening, outlet size and Colorbond colour when requesting a quotation. Lysaght technical staff can advise on sizing relative to box gutter discharge volume and AS 1562.3 hydraulic requirements. Colorbond Ultra provides enhanced coating durability compared to standard Colorbond — appropriate for coastal and high-corrosivity environments.
Technical Properties
- Fabricated from BlueScope Colorbond Ultra steel — enhanced coating system for superior corrosion resistance
- Custom widths 200–600mm, depths 100–250mm — fabricated to project specification
- DN90 and DN100 strap outlet collars — factory-formed for round downpipe connection
Limitations
- Custom fabrication — lead time must be confirmed with Lysaght branch before programming installation — not an off-the-shelf stock item
- Colorbond steel must not be in direct contact with copper or lead without appropriate isolation — dissimilar metal corrosion risk
- Rainwater head sizing must be confirmed by a hydraulic engineer for the catchment area — Lysaght can advise on fabrication dimensions but cannot provide a hydraulic design
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Stratco Colorbond Rainwater Head
Standard-size Colorbond steel rainwater head — Stratco
System Description
Stratco manufactures and supplies Colorbond steel rainwater heads in standard sizes suited to the majority of residential and light commercial box gutter applications. Standard sizes available are 200×150mm, 250×200mm, and 300×250mm — width × depth — with 90mm or 100mm outlet for standard round downpipe connection. All standard Colorbond colours are available so the rainwater head can be colour-matched to the adjacent gutter lining and downpipe system. Stratco rainwater heads are formed Colorbond steel with flanged inlet and outlet connections. Available through Stratco branches and selected roofing distributors nationally. For applications where the box gutter discharge volume requires a larger rainwater head than Stratco's standard range, a custom-fabricated unit from Lysaght or a specialist sheet metal fabricator should be specified. Confirm current standard size availability with Stratco before specifying — product range subject to revision.
Technical Properties
- Formed Colorbond steel rainwater head — standard sizes 200×150mm, 250×200mm, 300×250mm
- 90mm or 100mm outlet collar — matches standard round downpipe sizes
- All standard Colorbond colours available — colour-matched to adjacent gutter and downpipe
Limitations
- Standard sizes only — if the required rainwater head is larger than 300×250mm, a custom-fabricated unit must be specified
- Confirm current standard size range and availability with Stratco before specifying — product range subject to revision
- Colorbond steel must not be in direct contact with copper or lead without appropriate isolation
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Stramit Colorbond Rainwater Head
Colorbond steel rainwater head — Stramit — custom or standard
System Description
Stramit supplies BlueScope Colorbond steel rainwater heads in both standard and custom sizes for box gutter applications. Stramit's national distribution network covers metropolitan and regional areas across Australia, making it a practical supply option for projects in locations where other suppliers have limited branch coverage. Rainwater heads are supplied with DN90 and DN100 outlet collars for connection to standard round downpipes. The complete unit — inlet, body, and outlet — is manufactured in matching Colorbond colour to provide a uniform appearance with the adjacent gutter lining and downpipe system. Custom sizing is available where the box gutter discharge volume requires a rainwater head larger than standard. Confirm current product availability, standard sizes, custom fabrication lead time, and Colorbond colour options with the nearest Stramit branch before specifying. Stramit technical staff can assist with sizing guidance relative to the hydraulic design.
Technical Properties
- BlueScope Colorbond steel rainwater head — standard or custom sizing to project specification
- DN90 and DN100 outlet collars available — standard round downpipe connection
- Complete unit in matching Colorbond colour — inlet, body, and outlet colour-matched
Limitations
- Confirm current standard size range, custom fabrication capability, and lead time with Stramit before specifying
- Colorbond steel must not be in direct contact with copper or lead without appropriate isolation — dissimilar metal corrosion risk
- Rainwater head sizing must be confirmed by a hydraulic engineer for the catchment area
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of Colorbond steel rainwater head suppliers. Confirm all product selections against the current supplier before specifying.
| Supplier | Size range | Outlet DN | Colorbond colours available |
|---|---|---|---|
| Lysaght | Custom — 200–600mm wide, 100–250mm deep | DN90 / DN100 | All standard Colorbond colours |
| Stratco | Standard — 200×150, 250×200, 300×250mm | 90mm or 100mm | All standard Colorbond colours |
| Stramit | Standard and custom — confirm with branch | DN90 / DN100 | All standard Colorbond colours |
Do not confuse Colorbond rainwater heads with:
- Aluminium rainwater heads — aluminium rainwater heads are a separate product category requiring different fabrication and joining methods. Listed on the aluminium rainwater head page.
- Copper rainwater heads — copper rainwater heads are a heritage/premium specification requiring soldered seams and specialist fabrication. Listed on the copper rainwater head page.
- Stainless steel rainwater heads — AISI 316 stainless rainwater heads are specified for coastal and marine-zone environments. Listed on the stainless steel rainwater head page.
- Downpipes — rainwater heads are the transition box between the gutter outlet and the downpipe. They are not a substitute for correctly sized downpipes.
- Overflow scuppers or weirs — overflow scuppers are emergency overflow devices for box gutters and are a separate product category.
Disclaimer
Box gutter design must comply with AS 1562.3 and be sized by a licensed hydraulic engineer or roofing engineer for the catchment area. This page provides general technical information only. Final product selection must be confirmed against the current manufacturer technical data sheet, project specification, hydraulic design, and AS 1562.3 requirements. Do not rely on this reference as a substitute for professional engineering or roofing consultant advice.