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 compounds & detailing products?
Most balcony and roof leaks start at the details — penetrations, upstands, drains, internal corners and changes of plane. Flashing compounds and detailing products waterproof those junctions: liquid-applied fleece-reinforced PMMA/PU resins for complex 3-D details (some root-resistant for planters), brush-applied bituminous compounds for patching, stitch-bonded reinforcing fabric, and self-adhesive flashing tapes. They are detail components within the membrane system — selection turns on compatibility with the field membrane, the detail geometry, and root-resistance where planters/green roofs are involved.
Product Reference
Individual products — one card each — scroll to view all
Soprema
Soprema Alsan Flashing (RS 230 Flash)
Rapid-set PMMA liquid flashing resin (fleece-reinforced)
Soprema Alsan Flashing (ALSAN RS 230 Flash) is a rapid-setting PMMA liquid flashing resin combined with fleece to create a seamless, self-adhering, reinforced detail membrane for penetrations, upstands and complex roof details. Available in Australia via Bayset/Soprema.
Soprema
Soprema Alsan Flashing Quadro
1-part root-resistant PU liquid flashing resin
Soprema Alsan Flashing Quadro is a single-component, root-resistant polyurethane flashing resin for waterproofing junctions between horizontal surfaces, up-stands and roof details to the highest solicitation category (ETAG 005) — suited to green-roof and planter detailing.
Soprema
Soprema Alsan Flashing Jardin
1-part bitumen-PU flashing resin (UV/alkali/root-resistant)
Soprema Alsan Flashing Jardin is a single-component, ready-to-use, UV-, alkali- and root-resistant elastic bitumen-polyurethane flashing resin for waterproofing up-stands and roof details with anti-root penetration properties for green-roof and planter applications.
Tremco CPG Australia
Tremco Brushable Hydroseal
Heavy bituminous fibre-reinforced brush-applied sealing compound
Tremco Brushable Hydroseal is a heavy bituminous, fibre-reinforced, rust-inhibiting sealing compound applied thickly by brush for flashing details, patching and localised repairs. Reinforce large holes with Tremco PermAFab (mesh overlapped ≥150 mm); minimum 2 coats with the first dry before the second.
Tremco CPG Australia
Tremco PermAFab Reinforcing Fabric
Stitch-bonded polyester reinforcing fabric (for liquid membranes)
Tremco PermAFab is a 100% stitch-bonded polyester reinforcing fabric combining high tensile properties with good elongation for resistance to thermal stresses, embedded in a Tremco liquid waterproofing membrane (e.g. AlphaGuard BIO) to reinforce junctions, upstands and details.
ARDEX Australia
ARDEX Flashing Tape
Self-adhesive flashing tape (detailing)
ARDEX Flashing Tape is a self-adhesive flashing tape used to detail junctions, penetrations and terminations within the ARDEX waterproofing system. Confirm width, substrate and membrane overcoat compatibility against the current Ardex Australia TDS.
Generic
Generic Butyl / Aluminium Flashing Tape
Self-adhesive butyl / aluminium-faced flashing tape
Generic self-adhesive butyl / aluminium-faced flashing tape for detailing penetrations, laps and terminations, available in various formats (e.g. Crommelin and generic). Confirm the specific product, facing and membrane compatibility before specifying.
System Comparison
Flashing compounds & detailing — confirm all selections against the current manufacturer TDS before specifying.
Scroll the table sideways to see every column →
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.