The rain head that keeps storms outside your building.
When a downpipe blocks or a once-in-a-century storm hits, a Dam Buster rain head sends the overflow safely down the outside of your building. It's the only fully certified rain head range in Australia, and it works straight out of the box.
- ✓NCC conforming
- ✓Meets AS 3500.3
- ✓Rated for 1-in-100 year storms
- ✓Colorbond & specialised materials
What does a rain head actually do?
A rain head sits on the outside wall of a building, where a box gutter exits through the parapet. It has one job, and the third part of that job is where most rain heads on the market fall short.
Collects
Water from your box gutter discharges through the wall and into the rain head, on the outside of the building.
Directs
In normal rain, everything flows straight down the downpipe. You'll never notice it working.
Protects
In an extreme storm, or if the downpipe blocks completely, the excess spills safely over the front of the rain head and clear of the building.
Why it matters
Most rain heads sold in Australia are purely decorative. They lack the capacity to handle a blocked downpipe or a serious storm, and they fail to comply with mandatory Australian standards. This home owner's flood, and the insurance battle that followed, was caused by a single non-compliant rain head.
Every Dam Buster rain head is independently tested and certified to overflow safely in at least a 1-in-100 year storm event, anywhere from the tropics to the desert.
Unsure what size rainhead you need?
Enter your box gutter width and flow rate and we'll find your rainhead in seconds. No design tables required.
One rain head for every job.
Every model fits box gutters from 200 mm to 600 mm wide, carries the same certification, and can be adjusted to intermediate sizes on site. The differences come down to shape and fit. Here's how to pick.
R series
The go-to contemporary, rectangular rain head. Clean lines that suit modern builds, in sizes for every box gutter from 200 to 600 mm.
View dimensions →CR series
A round-fronted "Ned Kelly" profile for heritage and character homes, with the same engineering and certification underneath the classic curves.
View dimensions →Mini
An R-200 that's 75 mm lower in height. Made for porticos, awnings and other small roofs with lower flow rates and limited headroom.
View dimensions →Maxi
An R-300 that stands further off the wall, so the downpipe can fully clear a set-back, such as brick cladding below and lightweight panels above.
View dimensions →Stretch
R-200 and R-300 heads stretched horizontally to suit box gutters up to 600 mm wide, giving high capacity while keeping a slim profile on the facade.
View dimensions →Flat back
Built without the gutter receiver, so it fits odd-sized box gutters, round PVC outlets and eaves-gutter cut-ins. Add our adjustable box gutter adapter for a sealed, compliant fit on anything from 200 to 600 mm.
View dimensions →Any Colorbond colour. Almost any metal.
Standard range
Zincalume or Colorbond steel (0.55 BMT) across every size and product, in the full Colorbond palette with Matt finishes included. Made from Bluescope Australian steel.
Custom orders
Almost any flat metal can be used to suit your project:
- Stainless steel 304, or 316 marine grade for coastal builds
- Copper and Corten for architectural statements
- Galvanised steel and Colorbond Ultra for harsh environments
Ask an authorised licensee for a quote. Find one near you.
Jump straight to what you need.
Plumbers & roof plumbers
Eliminate callbacks. Install faster. Products that go in straight out of the box and comply first time.
→ How-to installation videos → Install manuals & guides → Find a local supplierArchitects & specifiers
Specify with confidence. Keep rain heads as small and discreet as the design deserves, with full NCC compliance evidence behind them.
→ Evidence of suitability → Performance solutions templates → Product dimensions & dataWant the detail? It's all here.
Everything below this line is for the people who like design tables: full specifications, compliance pathways, certification documents and interactive 3D models.
Sizing, selection and design detail.
Sizing & selection
- Models suit all box gutters from 200 mm to 600 mm wide. Intermediate sizes can be adjusted on site by the installing plumber. See the Installation Manual for details.
- Determine the 1:100 year ARI (1% AEP) flow rate for the roof being serviced, then select the rain head and downpipe combination from the Design Tables in the Installation Manual, available at Technical Downloads.
- Full physical dimensions for every model, including maximum box gutter sizing, are on the Product Dimensions page.
Flat back & adapters
- Flat back models delete the patented box gutter receiver, enabling fitment to odd-sized or shaped box gutters, round PVC outlets, and eaves gutter installations cut in on the side.
- All flat back rain heads can be supplied with an adjustable box gutter adapter (extra cost) ensuring a 100% positive, compliant seal on any box gutter between 200 and 600 mm. Three adapter sizes are available depending on application.
- Worked example for a 365 mm box gutter: Option A, R400 flat back plus adapter (465 × 600 × 325); Option B, R3-380 Stretch flat back plus adapter (445 × 450 × 245) for a lower profile.
R300 rain head (interactive 3D model)
R300 Stretch (interactive 3D model)
Certified. Independently tested. Documented.
Dam Buster rain heads meet or exceed the performance and overflow requirements of AS/NZS 3500.3, SA-HB39 and SA-HB114, along with all Conformance, Performance and Suitability requirements of the National Construction Code, including Volume 3. Dam Buster currently makes the only range of roof drainage products of this kind carrying that certification anywhere in Australia.
Compliance is achieved either as Deemed to Satisfy by Expert Judgement, based on Dam Buster's extensive technical documentation, or by means of a Performance Solution using our unique technical information and templates. All certification-critical documents are downloadable from Technical Downloads.
Note: certification methods vary by state or territory, so all products should be installed by a licensed professional, reflecting local regulator requirements.
None of these very common rain heads are compliant with mandatory Australian standards. What about yours?
These styles are sold every day across Australia. All of them fail the AS/NZS 3500.3 overflow requirements, and all are Non-Conforming Building Products under the NCC, which makes them an automatic fail for any plumbing audit.
Common questions.
Are Dam Buster rain heads compliant?
Absolutely yes. All Dam Buster products achieve full conformance and compliance with the relevant NCC Performance Requirements via two methods. Full details are under Compliance. Remember that "a Performance Solution is also compliance": if a proposed installation is considered outside Deemed to Satisfy, an appropriately prepared Performance Solution is a fully permitted alternative pathway.
All Dam Buster products meet the roof plumbing standards and codes across Australia, including AS/NZS 3500.3:2021 and all previous versions. For Victoria, the VBA has specifically advised (Fact Sheet, March 2023) that it is satisfied as long as products are fit for purpose and meet the relevant Performance Requirements of NCC Volume Three. All Dam Buster products do, along with the NCC Volume 1 and 2 requirements in every other state and territory.
One warning: fake copies of Dam Buster products meet no standards at all and are an automatic audit fail. Only buy from an authorised licensee.
How do I work out what size rain head I need?
The fast way: use our Rainhead Selector. Enter your box gutter width and flow rate and it does the rest.
The full method: follow our Quick Design Guide from pages 3 to 13. Use Method A or B to calculate your 1% AEP, calculate your flow rate from your catchment area (page 6), then size from the table on page 13. AS 3500.3 has required these calculations for all roof drainage design nationally since 1998, whichever brand of product you use. Read every step carefully, because skipping them will likely result in a non-compliant system.
Can Dam Buster rain heads be used with uncommon box gutter widths?
Absolutely. Flat back versions accommodate box gutters up to 600 mm wide as per NCC requirements, and the Stretch series provides a lower-profile head with the capacity of a much larger R-series model. For example, a 365 mm box gutter can take an R400 flat back with adapter (465 × 600 × 325) or an R3-380 Stretch flat back with adapter (445 × 450 × 245).
Do Dam Buster rain heads install the same way as other rain heads?
They're usually simpler and faster to install. Installers should still read the installation guide carefully to ensure a compliant result. The most common mistake is letting the box gutter protrude into the main body of the rain head. The box gutter should finish flush with the rain head's back panel.
The only box gutter drainage solution you'll ever need.
Australian designed, Australian made, protected by Australian and international patents, and available from suppliers across the country.
Find a local supplier