Repair Systems — Roofing Defects
Scupper outlet systems for roof overflow compliance
Scupper outlets are wall-mounted overflow devices required by AS/NZS 3500.3 to prevent roof flooding in the event of primary drainage blockage. Stainless steel and aluminium scupper bodies are set at 25–50mm above the primary drain level to activate only during emergency overflow.
What are scupper overflow systems?
Scupper overflow systems are wall-mounted secondary drainage outlets installed through the parapet wall of flat and low-pitched roofs. They are required by AS/NZS 3500.3 to provide emergency overflow drainage in the event that primary roof drains become blocked. The scupper inlet is set at 25–50mm above the primary drain invert level, ensuring the system activates only during an emergency overflow event and does not intercept normal rainfall drainage.
Product Reference
3 products — stainless steel and aluminium scupper overflow outlets — scroll to view all
Blucher Scupper Outlet S300
Stainless steel wall-mounted scupper overflow outlet
System Description
The Blucher Scupper Outlet S300 is a wall-mounted secondary overflow outlet manufactured from AISI 316 stainless steel, designed for flat and low-pitched roof drainage compliance under AS/NZS 3500.3. The scupper body passes through the parapet wall and is sized to activate at 25–50mm above the primary drain invert level, providing emergency overflow capacity in the event of primary drain blockage. The adjustable height sleeve allows the scupper to be set precisely during construction or membrane installation, accommodating varying membrane and screed thicknesses. The open-face inlet is designed to resist debris ingress while maintaining the required hydraulic capacity. Available in outlet sizes from 75×50mm through to 150×75mm. Confirm the current product range, sizing, and installation requirements with Blucher Australia technical before specifying.
Technical Properties
- AISI 316 stainless steel body — corrosion resistant for external and coastal roof applications
- Available sizes: 75×50mm to 150×75mm outlet face — confirm sizing against hydraulic calculation
- Adjustable height sleeve — accommodates membrane and screed thickness variation during installation
Limitations
- Must be installed at the correct overflow activation height — 25–50mm above primary drain invert — incorrect height renders overflow system non-compliant
- Waterproofing membrane must be correctly terminated and sealed at the scupper body — flanged connection or formed lead seal required
- Not a primary drainage outlet — do not use as a primary roof drain or box gutter outlet
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Geberit wall scupper D110
Stainless steel wall scupper — DN110 — membrane connection flange
System Description
The Geberit wall scupper D110 is a stainless steel wall-mounted overflow outlet with a DN110 discharge connection, designed for secondary overflow compliance on flat roofs and parapet-bounded roof areas. The integrated membrane connection flange allows the waterproofing membrane to be bonded directly to the scupper body, forming a continuous waterproof connection at the through-wall penetration. The D110 is compatible with Geberit siphonic roof drainage systems, making it suitable for specification alongside Geberit primary drainage where a consistent drainage system from one supplier is required. Install at 25–50mm above the primary drain invert per AS/NZS 3500.3 overflow requirements. Confirm the current product range, fixing details, and membrane compatibility with Geberit Australia before specifying.
Technical Properties
- Stainless steel body — DN110 discharge outlet — suitable for through-parapet overflow installation
- Integrated membrane connection flange — provides positive waterproofing membrane connection at scupper body
- Compatible with Geberit siphonic roof drainage systems — consistent system specification available from one supplier
Limitations
- Must be set at the correct overflow activation height — 25–50mm above primary drain invert — confirm against hydraulic design
- Membrane flange must be correctly bonded to the waterproofing membrane — confirm compatibility with the membrane system specified
- Not a primary drainage outlet — DN110 discharge sizing is for overflow only — confirm hydraulic capacity with hydraulic engineer
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Alproc aluminium scupper
Extruded aluminium wall scupper — custom width — powder-coated
System Description
The Alproc aluminium scupper is an extruded aluminium wall-mounted overflow outlet available in custom widths from 100mm to 300mm, making it suitable for architectural applications where a wide overflow opening is required to achieve the necessary hydraulic capacity or to match parapet aesthetics. The scupper body is powder-coated in the Colorbond range, allowing it to be colour-matched to roof flashings, gutters, and cladding. The integral back flange provides a positive connection point for waterproofing membrane termination at the through-wall penetration. The low-profile outlet minimises visual impact on the parapet face. Suitable for flat roofs, low-pitched roofs, and architectural parapets where custom width is required. Confirm current product specifications, powder-coat colour options, and membrane compatibility with Alproc Australia before specifying.
Technical Properties
- Extruded aluminium body — custom widths 100–300mm — suitable for architectural and standard overflow applications
- Powder-coated finish — Colorbond range available — colour-match to roof flashings and cladding
- Integral back flange — provides waterproofing membrane connection at scupper body penetration
Limitations
- Aluminium — confirm suitability for coastal or aggressive environments — may require anodising or marine-grade powder coating in severe marine zones
- Custom width must be confirmed against hydraulic sizing calculation — wider scupper does not automatically mean compliant capacity
- Integral back flange must be correctly bonded to the membrane system — confirm membrane compatibility with Alproc before specifying
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of scupper overflow outlet systems. Confirm all product selections against the current manufacturer TDS before specifying.
| Product | Brand | Material | Outlet size | Membrane connection | Adjustability |
|---|---|---|---|---|---|
| Scupper Outlet S300 | Blucher | AISI 316 stainless steel | 75×50mm to 150×75mm | Adjustable sleeve — formed or flanged at site | Adjustable height sleeve |
| Wall scupper D110 | Geberit | Stainless steel | DN110 | Integral membrane connection flange | Fixed — set height at installation |
| Aluminium scupper | Alproc | Extruded aluminium — powder-coated | Custom 100–300mm width | Integral back flange for membrane | Fixed — custom width selection |
Do not confuse scupper systems with:
- Pipe overflow systems — vertical or angled pipe outlets installed through the parapet at a set height above primary drainage — a different overflow mechanism to a wall-mounted scupper body
- Weir overflow outlets — proprietary adjustable weir devices positioned at the emergency overflow level — not a scupper body and not a through-wall pipe
- Primary roof drains — puddle flanges and primary drainage outlets are not overflow devices and must not be confused with secondary overflow scuppers set above primary drain level
- Box gutter outlets — primary outlets at the base of a box gutter are primary drainage, not overflow scuppers — overflow must be separate and at the correct activation height
Disclaimer
This page provides general technical information only. Final product selection must be confirmed against the current manufacturer technical data sheet, project specification, substrate condition, exposure level, drainage design, NCC requirements, AS/NZS 3500.3 requirements, and applicator warranty conditions. Do not rely on this reference as a substitute for professional engineering or hydraulic consultant advice.