Repair Systems — 01
Flashing compound systems — roofs and balconies
Technical product reference for liquid PU-bitumen flashing compounds, bituminous brushable compounds, and self-adhesive flashing tapes used to seal upstands, parapet junctions, penetrations, and detail areas on roofs and balconies in Australian Class 2 strata building remediation.
What are flashing compound systems — roofs and balconies?
Flashing compound systems are liquid-applied or self-adhesive waterproofing products used to seal and waterproof upstands, parapet wall junctions, roof-to-wall interfaces, penetrations, step junctions, and other detail areas on roofs and balconies where a sheet membrane cannot be easily applied, heat-bonded, or formed into a watertight junction. On torch-on modified bitumen sheet membrane systems — the dominant sheet membrane system in Australian strata building remediation — the sheet membrane covers the horizontal field of the roof or balcony, but the junctions with vertical upstands, parapet walls, step flashings, and penetrations require a separate compound or flashing product to complete the waterproof detail. Flashing compounds bridge the gap between the field membrane and the vertical surface, conforming to irregular substrates and complex geometry that sheet membranes cannot reach.
Flashing compound systems are also used as standalone repair compounds on existing waterproofing systems — applied over failed or cracked existing membrane at upstands, corners, and penetration perimeters where the primary membrane has failed but full replacement is not required or is not yet scheduled. In this repair role, flashing compounds extend the service life of an existing system at its most vulnerable detail locations.
The three primary flashing compound types used in Australian roof and balcony waterproofing remediation are liquid PU-bitumen flashing compounds, bituminous brushable compounds, and self-adhesive flashing tapes. Each has a distinct substrate compatibility, membrane system compatibility, UV resistance, and application method. The correct flashing compound must be selected to match the primary membrane system it is used with — flashing compounds are not universally interchangeable across membrane systems and brands.
Liquid and Compound Flashing Product Reference
4 products — single-component PU-bitumen resin, bituminous rubber compound — upstands, parapet bases, wall junctions, penetration perimeters, and step detail waterproofing on roofs and balconies
Soprema Alsan Flashing
Single-component polyurethane-bitumen liquid flashing resin — UV resistant — exposed grade
Single-component PU-bitumen liquid flashing resin — UV resistant — can be left exposed without cap sheet or metal flashing above — brush or roller — no primer on most substrates — 100% compatible with SBS and APP bituminous sheet membrane systems — 19L pail
Specifier Note
Confirm membrane system compatibility and reinforcing fleece requirements with Soprema Australia before specifying. For non-bituminous systems (ARDEX, Mapei liquid-applied PU), confirm compatibility directly with Soprema Australia — Alsan Flashing is not automatically approved over non-bituminous field membranes.
System Description
Soprema Alsan Flashing is a patented single-component, ready-to-use polyurethane-bitumen waterproofing resin used to waterproof hard-to-access upstands and detail junctions where applying sheet waterproofing membranes is difficult or impractical. It is applied by brush or roller in 2–3 coats directly to the substrate — no primer or catalyst required on most surfaces. UV resistant and can be left exposed without additional protection — an important advantage over bituminous compounds that require a cap sheet or metal flashing above if exposed to UV.
On torch-on modified bitumen sheet membrane systems, Alsan Flashing is applied at upstands, parapet wall bases, step junctions, and penetration perimeters — locations where the torch-on sheet cannot be heat-bonded to a vertical surface without risk and where a liquid compound is more practical. The compound is 100% compatible with bituminous sheet membrane systems — it bonds directly to torch-on SBS and APP modified bitumen membranes without a separate adhesive or primer.
Applied in 2–3 coats with reinforcing fleece (Alsan Polyfleece) embedded between coats at corners, angles, and penetration perimeters. The fleece is mandatory at any change of plane — do not apply without fleece at internal or external angles. Cure time is dependent on temperature and humidity — confirm with Soprema Australia before applying in cold or humid conditions.
Available in Australia through Bayset and The Waterproofing Shop in 19L pails.
Technical Properties
- Single-component PU-bitumen liquid resin — ready to use — no catalyst or primer required on most substrates
- UV resistant — can be left exposed without cap sheet or metal flashing above
- Applied by brush or roller in 2–3 coats
- Reinforcing fleece (Alsan Polyfleece) required at all changes of plane, corners, and penetration perimeters
- 100% compatible with SBS and APP modified bituminous sheet membrane systems
- Cures to a dark brown finish — can be finished with hand-cast minerals to match surrounding granule surfacing
- Suitable for: upstands, parapet walls, penetration perimeters, step junctions, roof-to-wall interfaces, gutter upstands
- Available in 19L pail through Bayset and The Waterproofing Shop — confirm current availability before specifying
Limitations
- Bituminous membrane system primary — confirm compatibility with liquid-applied PU and single-ply membrane systems with Soprema Australia before applying over non-bituminous systems
- Reinforcing fleece is mandatory at all angles and penetration perimeters — do not apply without fleece at these locations
- Cures to dark brown — not suitable where a light colour finish is required in an exposed position
- Confirm cure time with Soprema Australia for cold or humid conditions before applying
- Confirm current product availability, pricing, and lead times with Bayset or Soprema Australia before specifying
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Soprema Alsan Flashing Quadro
Single-component polyurethane resin — cold-applied — flameless — dark grey
Single-component polyurethane resin — cold-applied flameless — dark grey (RAL 7012) — no catalyst or activator required — for occupied strata remediation where hot-work is restricted — Soprema bituminous system compatible — used in Bayset System 510
Specifier Note
Confirm Soprema system compatibility and current Australian availability with Soprema Australia or Bayset before specifying. Alsan Fleece 165B reinforcing fabric must be embedded between coats at all corners, angles, and penetration perimeters — not optional.
System Description
Soprema Alsan Flashing Quadro is a single-component polyurethane resin liquid flashing compound used at upstands, parapet bases, and detail interfaces on roofs and balconies. It is cold-applied with no catalyst or activator required — applicable at any time of year and across a wide temperature range without affecting performance. Unlike torch-on flashing details, Alsan Flashing Quadro involves no flame and no heat — eliminating the hot-work permit requirement at the flashing detail. This is particularly valuable on occupied strata building remediation where hot-work restrictions apply.
Alsan Flashing Quadro is used in conjunction with Soprema bituminous membrane systems as the upstand and detail compound. It is applied with Alsan Fleece 165B reinforcing fabric embedded between coats at all corners and changes of plane. Alsan Flashing Quadro is specified as the detail compound in Bayset's documented planter box waterproofing System 510 (used with Soprema Colphene 3000 self-adhesive sheet membrane). It can also be applied directly to concrete, wood, bitumen, PVC, and many metal surfaces.
Available in dark grey (RAL 7012) — can be finished with hand-cast minerals to create a consistent finish with the surrounding membrane. Confirm current Australian product availability and pricing with Soprema Australia or Bayset before specifying.
Technical Properties
- Single-component polyurethane resin — no catalyst or activator required
- Cold-applied — flameless — no hot-work permit required
- Applied in 2–3 coats — Alsan Fleece 165B embedded between coats at corners and changes of plane
- Compatible substrates: concrete, wood, bitumen, PVC, and many metals
- Used with Soprema bituminous membrane systems as upstand and detail compound — specified in Bayset System 510
- Dark grey (RAL 7012) — can be finished with hand-cast minerals
- Suitable for: upstands, parapet walls, planter box walls, detail junctions, and penetration perimeters
- Flameless — appropriate for occupied strata building remediation where hot-work is restricted
Limitations
- Soprema system primary — confirm compatibility with non-Soprema membrane systems with Soprema Australia before applying
- Alsan Fleece 165B embedded reinforcement is mandatory at all angles and penetration perimeters
- Confirm current Australian product availability, pricing, and lead times with Soprema Australia or Bayset before specifying
- Dark grey finish — not for applications requiring a light colour without an additional coating above
- Confirm UV resistance and exposure classification with Soprema Australia for extended exposed applications
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Soprema Alsan Flashing Jardin
Single-component PU-bitumen liquid flashing resin — anti-root and rhizome resistant
Single-component PU-bitumen resin with anti-root and rhizome-resistance properties — for waterproofing upstands, planter box walls, and roof edge details on green roofs and planted podium applications where root penetration at the vertical face is a risk
Specifier Note
Confirm root resistance certification, membrane system compatibility, and Australian availability with Soprema Australia before specifying. The horizontal membrane must also be independently root-resistant — Alsan Flashing Jardin covers the vertical face only.
System Description
Soprema Alsan Flashing Jardin is the root and rhizome-resistant variant of the Alsan Flashing family — a single-component, ready-to-use bitumen-polyurethane resin specifically formulated for waterproofing upstands, planters, roof edges, and difficult detail areas on green roofs and planted podium applications where root and rhizome penetration resistance is required at the vertical face as well as the horizontal membrane.
On green roof and podium planter applications, the FLL-certified horizontal membrane (Wolfin, Cosmofin, or Soprema Colphene 3000) provides root resistance across the floor of the planter. However, the vertical upstand faces — planter box walls, parapet bases, and step junctions — require a root-resistant flashing compound to maintain the integrity of the root barrier system at the detail. Alsan Flashing Jardin addresses this vertical face root resistance requirement.
Applied by brush or roller in 2–3 coats with reinforcing fleece at angles and changes of plane. Confirmed at soprema.com.au Australian product pages. Confirm current product availability, pricing, and lead times with Soprema Australia before specifying.
Technical Properties
- Single-component PU-bitumen liquid resin — anti-root and anti-rhizome penetration properties
- Applied by brush or roller in 2–3 coats — reinforcing fleece required at all angles and changes of plane
- For: planter box walls, green roof upstands, parapet bases, and roof edge details on planted podium applications
- No primer required on most substrates
- For use with Soprema green roof and planter system products — confirmed at soprema.com.au
- Addresses vertical upstand face root resistance — must be used with a root-resistant horizontal membrane below
Limitations
- Soprema green roof and planter system primary — confirm compatibility with non-Soprema membrane systems with Soprema Australia before applying
- Root resistance is at the vertical upstand face — the horizontal membrane must also be root-resistant (see Root Resistant Membranes page)
- Confirm current Australian product availability with Soprema Australia before specifying
- Confirm reinforcing fleece requirements at angles and penetration perimeters with Soprema Australia
- Confirm root resistance certification and FLL compliance status with Soprema Australia for the specific planted application
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Tremco Brushable Hydroseal
Heavy bituminous fibre-reinforced sealing compound — brush applied — rust inhibiting
Heavy bituminous fibre-reinforced rust-inhibiting sealing compound — applied thickly by brush at lap joints, upstands, metal flashing bedding, pipe penetration perimeters, and general joint sealing — not UV resistant as a standalone exposed product
Specifier Note
Not UV resistant in exposed positions — a metal flashing or cap sheet must be applied above Brushable Hydroseal in any location exposed to direct sunlight or weathering. Confirm UV exposure status before specifying.
System Description
Tremco Brushable Hydroseal is a heavy bituminous, fibre-reinforced, rust-inhibiting sealing compound specifically designed to be brushed thickly onto any surface requiring a flexible, bituminous waterproof seal. It is used at roof lap joints, upstand sealing details, metal flashing bedding, pipe penetration perimeters, and as a general sealing compound under and around metal flashings on flat roof and balcony applications.
In Australian strata roof and balcony remediation, Brushable Hydroseal is used where a heavy-body bituminous compound is required to seal a joint, bridge a gap, or bed a metal flashing before a torch-on sheet membrane is applied above. The fibre reinforcement provides flexibility and crack-bridging capability beyond plain bituminous paint products.
Not UV resistant as a standalone exposed product — where applied in an exposed position, a cap sheet, metal flashing, or other UV-resistant covering must be applied above. Confirm the application detail and UV exposure status with the project specification and Tremco technical before using in an exposed position without additional covering.
Technical Properties
- Heavy bituminous compound — fibre reinforced — rust inhibiting
- Applied thickly by brush — heavy body application — no mixing required
- Suitable substrates: steel, concrete, and masonry
- Used at: lap joints, upstand sealing, metal flashing bedding, pipe penetration perimeters, joint sealing
- Rust inhibiting — suitable for sealing around metal components and on steel substrates
- Tremco Australia — confirmed product at tremco.com.au
Limitations
- Not UV resistant as a standalone exposed product — metal flashing or cap sheet required above in any exposed position
- Not a primary field membrane — a sealing and bedding compound for detail locations only
- Confirm substrate preparation and primer requirements with Tremco technical before applying to non-standard substrates
- Confirm current product specification, formulation, and availability with Tremco Australia before specifying
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Self-Adhesive Flashing Tape Product Reference
3 products — butyl rubber, aluminium-faced bitumen, and reinforced polyethylene — for joint sealing, pipe penetration flashing, lap sealing, and critical detail waterproofing on roofs and balconies
ARDEX Flashing Tape
Self-adhesive tape — ARDEX Weldtec system component — 100mm × 4.7m
Self-adhesive flashing tape — 100mm wide × 4.7m roll — ARDEX Weldtec membrane system component — adhered with ARDEX WA 98 adhesive — Weldtec membrane heat-welded or glued over tape after installation — for joints, pipe flashings, and critical details
Specifier Note
ARDEX Weldtec system component only — confirm this is the correct product for the ARDEX Weldtec membrane system being specified. ARDEX WA 98 adhesive is required for bonding — the flashing tape cannot be applied without WA 98.
System Description
ARDEX Flashing Tape is a self-adhesive tape product used within the ARDEX Weldtec membrane system for waterproofing joints, pipe flashings, sealing mouldings in gussets, securing pipe flashings, and handling challenging or awkward construction scenarios. The tape is cut to size and adhered to the prepared substrate using ARDEX WA 98 adhesive during installation. Once correctly positioned and adhered, the ARDEX Weldtec membrane is then glued or heat-welded over the flashing tape to create a seamless waterproofing membrane system at and around critical detail areas.
The ARDEX Flashing Tape is a system component — it is designed to work within the ARDEX Weldtec membrane system and is not a standalone waterproofing product. The tape provides a substrate preparation and reinforcement function at detail areas before the Weldtec membrane is applied over the top. Available in 100mm wide × 4.7m roll format. Confirm current availability and pricing with ARDEX Australia or trade stockists before ordering.
Technical Properties
- Self-adhesive flashing tape — 100mm wide × 4.7m roll
- Used within the ARDEX Weldtec membrane system — system component, not a standalone waterproofing product
- Adhered to prepared substrate using ARDEX WA 98 adhesive
- ARDEX Weldtec membrane is glued or heat-welded over the tape after installation
- For: joints, pipe flashings, sealing gussets, and awkward construction details within the Weldtec system
- Available through ARDEX Australia and trade stockists — confirm current availability before ordering
Limitations
- ARDEX Weldtec system component only — not for use as a standalone waterproofing tape without the Weldtec membrane applied over
- ARDEX WA 98 adhesive required for substrate bonding — the tape is not directly self-adhesive without WA 98
- Confirm current product availability, roll format, and system specification with ARDEX Australia before specifying
- Do not use as a substitute for reinforcing fabric (Deckweb) in standard ARDEX liquid-applied membrane systems — the flashing tape is for the Weldtec system specifically
- Confirm the tape is the correct format for the specific ARDEX Weldtec application with ARDEX technical before ordering
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Tremco PermAFab
Self-adhesive reinforced flashing tape — Tremco Australia
Self-adhesive reinforced flashing tape — for lap sealing, joint bridging, and pipe penetration flashing on roofing and balcony waterproofing applications — Tremco system compatible — available through Bowens Australia and Tremco trade supply
Specifier Note
Confirm the correct Tremco flashing tape product and system application with Tremco Australia before ordering. Multiple tape formats are available — confirm the specific product for the membrane system and application.
System Description
Tremco PermAFab is a self-adhesive reinforced flashing tape used for lap sealing, joint bridging, and pipe penetration flashing on roofing and balcony waterproofing applications in Australian strata and commercial construction. Confirmed available through Bowens building supply in Australia. Applied by pressing directly onto the prepared substrate — the self-adhesive backing bonds to the surface and provides immediate waterproofing at the joint or penetration.
PermAFab is used in conjunction with Tremco roofing and waterproofing membrane systems as a system-specific flashing and detail tape. It can also be used as a repair tape on existing roofing systems for lap sealing and joint bridging at failed joints or penetrations. Confirm the correct Tremco system specification for the specific application before ordering — Tremco produces multiple flashing and tape products within its roofing range.
Technical Properties
- Self-adhesive reinforced flashing tape — pressed directly onto prepared substrate
- For: lap sealing, joint bridging, pipe penetration flashing on roofing and balcony applications
- Used with Tremco roofing and waterproofing membrane systems as a system flashing detail tape
- Available through Bowens Australia and Tremco trade supply — confirmed Australian stockist
- Can also be used as a repair tape on existing roofing systems at failed laps and joints
Limitations
- Confirm the correct Tremco flashing tape product for the specific membrane system and application — Tremco produces multiple tape formats
- Confirm substrate preparation requirements with Tremco technical before applying
- Not a standalone primary waterproofing product — used at detail and joint locations within a Tremco system
- Confirm current product availability, width, and roll length with Tremco Australia or Bowens before ordering
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Generic Butyl / Aluminium Flashing Tape
Self-adhesive butyl rubber or aluminium-faced bitumen tape — trade supply — multiple brands
Self-adhesive butyl rubber or aluminium-faced bitumen flashing tape — widely available through trade waterproofing suppliers — for pipe penetration sealing, joint bridging, and minor flashing repairs — confirm compatibility with the primary membrane system before applying
Specifier Note
Confirm membrane system compatibility before applying generic trade tapes — system-specific flashing tapes are preferred for full strata remediation work under manufacturer warranty. Generic tapes are appropriate for minor repair, maintenance, and residential detail work.
System Description
Self-adhesive butyl rubber and aluminium-faced bitumen flashing tapes are widely available through Australian waterproofing and building trade suppliers under multiple brand names (Crommelin, Gripset, and generic trade supply). These tapes are used for pipe penetration sealing, joint bridging, minor flashing repairs, and general detail waterproofing on residential and light commercial roofing and balcony applications.
The butyl rubber format provides a highly conformable, permanently flexible seal at joints and penetrations — butyl remains flexible in cold conditions and bonds to a wide range of substrates. The aluminium-faced bitumen format provides a more rigid, UV-resistant tape suitable for exposed flashing and lap sealing applications on roofing where a dimensionally stable tape is preferred.
These generic trade tapes are appropriate for minor repair, maintenance, and residential detail work. For Class 2 strata remediation, confirm that the tape is appropriate for the specific membrane system and substrate before applying — system-specific flashing tapes (ARDEX Flashing Tape, Tremco PermAFab) are preferred where the work is part of a full membrane system remediation under a manufacturer warranty.
Technical Properties
- Butyl rubber format: highly conformable — permanently flexible — bonds to a wide range of substrates in cold and warm conditions
- Aluminium-faced bitumen format: dimensionally stable — UV resistant — suitable for exposed flashing and lap sealing
- For: pipe penetration sealing, joint bridging, minor flashing repairs, general detail waterproofing
- Multiple brands — Crommelin, Gripset, and generic trade supply — widely available nationally
- Applied by pressing directly onto prepared substrate — self-adhesive backing — immediate waterproofing at detail
Limitations
- Not a primary field membrane — detail and repair application only
- Confirm compatibility with the primary membrane system before applying — generic tapes may not be compatible with all membrane systems under manufacturer warranty
- For Class 2 strata remediation under a manufacturer system warranty, use system-specific flashing tapes (ARDEX, Tremco) rather than generic trade tapes
- Confirm substrate preparation and primer requirements with the tape supplier before applying
- Confirm current product availability, width, roll length, and format with local supplier before ordering
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Flashing Compound and Tape System Comparison
Side-by-side comparison — Part A: liquid and compound flashing systems, Part B: self-adhesive flashing tapes. Confirm all product selections against the current manufacturer TDS before specifying.
Part A — Liquid and Compound Flashing Systems
| Product | Brand | Type | UV exposed | Reinforcement required | Membrane compatibility | Key restriction |
|---|---|---|---|---|---|---|
| Alsan Flashing | Soprema | Single-component PU-bitumen liquid resin | Yes — UV resistant — can be left exposed | Yes — Alsan Polyfleece at all angles and penetrations | 100% compatible with SBS and APP bituminous sheet systems — confirm with non-bituminous systems | Dark brown cure — reinforcing fleece mandatory at angles — confirm compatibility with non-bituminous systems |
| Alsan Flashing Quadro | Soprema | Single-component PU resin — cold-applied | Yes — UV resistant | Yes — Alsan Fleece 165B at angles and penetrations | Soprema bituminous systems primary — used in Bayset System 510 | Flameless — no hot-work permit — confirm compatibility with non-Soprema systems — dark grey (RAL 7012) |
| Alsan Flashing Jardin | Soprema | Single-component PU-bitumen — root and rhizome resistant | Confirm with Soprema | Yes — reinforcing fleece at angles | Soprema green roof and planter systems | Root resistance at vertical upstand face — horizontal membrane must also be root-resistant — confirm Australian availability |
| Brushable Hydroseal | Tremco | Heavy bituminous fibre-reinforced compound | No — UV cover required above in exposed positions | No — applied thickly as single layer | Tremco bituminous systems — general sealing and bedding | Not UV resistant exposed — metal flashing or cap sheet required above — rust inhibiting — sealing and bedding compound only |
Part B — Self-Adhesive Flashing Tapes
| Product | Brand | Type | UV exposed | System specificity | Key restriction |
|---|---|---|---|---|---|
| ARDEX Flashing Tape | ARDEX Australia | Self-adhesive tape — 100mm × 4.7m — Weldtec system | No — Weldtec membrane applied over tape | ARDEX Weldtec system specific — not standalone | Requires ARDEX WA 98 adhesive for bonding — Weldtec membrane must be applied over — not for other ARDEX membrane systems |
| Tremco PermAFab | Tremco Australia | Self-adhesive reinforced tape | Confirm with Tremco | Tremco system compatible | Confirm correct Tremco tape product for specific membrane and application — multiple tape formats available — confirm with Tremco Australia |
| Generic Butyl / Aluminium Tape | Crommelin / Gripset / various | Self-adhesive butyl rubber or aluminium-faced bitumen | Aluminium-faced format: UV resistant | General trade — not system specific | Not for primary field waterproofing — system-specific tapes preferred for full strata remediation under warranty — confirm membrane compatibility before applying |
Flashing compounds are detail products — they do not replace the field membrane
Flashing compounds and self-adhesive flashing tapes are detail products — they seal upstands, parapet bases, penetration perimeters, and step junctions. They are not field membrane products and must not be applied across the horizontal field of a roof or balcony as a substitute for the primary membrane system. A roof or balcony waterproofed only with flashing compound at details but without a correctly applied field membrane will fail — the flashing compound coverage is insufficient to provide the required waterproofing across the field area. Every correctly specified roof or balcony waterproofing system includes both a field membrane (torch-on sheet, single-ply, or liquid-applied) and a compatible flashing compound at all detail locations. Both are mandatory — neither replaces the other.
Reinforcing fleece is mandatory at all angles and penetration perimeters with liquid flashing compounds
Soprema Alsan Flashing, Alsan Flashing Quadro, and Alsan Flashing Jardin must all be applied with the correct reinforcing fleece (Alsan Polyfleece or Alsan Fleece 165B) embedded between coats at all internal and external angles, changes of plane, and penetration perimeters. Applying liquid flashing compound without embedded fleece at these locations produces a thin, unreinforced film that will crack under thermal movement at the angle — the most common location for liquid flashing compound failure. The fleece is not optional at angles — do not apply liquid flashing compound to any angle or change of plane without reinforcing fleece embedded between the first and second coats.
Confirm flashing compound compatibility with the primary membrane system before specifying
Flashing compounds must be compatible with the primary field membrane being used on the project. Soprema Alsan Flashing is 100% compatible with SBS and APP bituminous sheet membranes — it is not automatically compatible with ARDEX or Mapei liquid-applied PU membranes. ARDEX Flashing Tape is a Weldtec system component — it is not for use in other ARDEX membrane systems. Tremco PermAFab is designed for Tremco roofing systems. Using a flashing compound from a different manufacturer's system than the field membrane — or using a system-specific flashing tape in a non-compatible system — risks adhesion failure at the detail junction and may void the membrane system warranty. Always confirm flashing compound compatibility with the field membrane manufacturer before specifying.
Upstand height must meet AS 3740 and AS 4654 minimums — flashing compound must extend to the required height
The flashing compound applied at upstands, parapet bases, and wall junctions must extend to the minimum height required by AS 3740:2021 (for balcony and wet area applications) and AS 4654.2 (for roof membrane applications). For balcony applications, the minimum upstand height is typically 150mm above the finished floor level. The flashing compound must cover the full upstand height from the base — integrating with the field membrane — to the minimum required height on the vertical face. A flashing compound that terminates below the design upstand height leaves an unsealed gap between the top of the flashing and the wall surface — a direct water ingress path. Measure and mark the minimum upstand height on the wall before applying the flashing compound, and verify the height is achieved before the system is covered.
Disclaimer
This page provides general technical information only. Final product selection must be confirmed against the current manufacturer technical data sheet, project specification, primary membrane system compatibility, substrate condition, UV exposure status, upstand height requirements per AS 3740:2021 and AS 4654.2, NCC requirements, and reinforcing fleece requirements. Flashing compounds are detail products used in conjunction with a primary field membrane — they do not replace the field membrane. Reinforcing fleece is mandatory at all angles and penetration perimeters with liquid flashing compounds. Do not rely on this reference as a substitute for professional waterproofing consultant advice.