Repair Systems — 03 — Facade & External Envelope
Breathable & vapour-permeable render systems
Technical product reference for breathable and vapour-permeable render systems with low sd values used in facade remediation on Australian masonry facades where moisture vapour release through the render is required. Covers product classification, system selection, and brand comparisons.
What are breathable vapour-permeable render systems?
Breathable vapour-permeable renders are cementitious render systems engineered with a high pore volume and low sd (vapour diffusion resistance) value that allows moisture vapour to migrate through the render body and escape from the facade surface without causing blistering, delamination, or efflorescence.
Product Reference
3 products — 3 brands — breathable vapour-permeable render systems — scroll to view all
Remmers Feinputz SP (Breathable Finish Render)
Vapour-permeable fine finish render — low sd value — exterior masonry
System Description
Remmers Feinputz SP is a vapour-permeable fine finish render with a low sd value (sd <0.14m — confirm from TDS) and high pore volume (>35% — confirm from TDS) designed for exterior masonry facades where moisture vapour release is required. It is used as the finish render in breathable render systems on salt-affected and heritage facades where trapping moisture vapour behind the render surface would cause delamination or damage. Confirm sd value, pore volume, WTA classification, and full system specification with Remmers Australia technical. TODO: owner confirm — Remmers Feinputz SP sd value, pore volume, WTA status and Australian availability.
Technical Properties
- Vapour-permeable finish render — low sd value (confirm <0.14m from TDS)
- High pore volume (confirm >35% from TDS)
- Suitable for exterior masonry where moisture vapour release is required
Limitations
- Not a waterproofing system — breathable renders allow vapour transmission
- Not suitable where moisture ingress source has not been treated
- TODO: owner confirm — Remmers Feinputz SP specification, sd value, pore volume and WTA status in Australia
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Parex Breathable Render System
Breathable vapour-permeable render — exterior masonry
System Description
Parex (distributed in Australia by Alumasc Building Products) supplies breathable render systems for exterior masonry facades. Confirm the specific Parex product for breathable vapour-permeable render application with Parex/Alumasc technical — the Parex range includes renders with varying sd values and pore volumes. TODO: owner confirm — specific Parex product for breathable vapour-permeable render, sd value, pore volume and Australian availability.
Technical Properties
- Vapour-permeable render — confirm sd value from TDS with Parex/Alumasc
- Exterior masonry facades
- Apply over compatible primer and base coat — confirm with Parex
Limitations
- TODO: owner confirm — specific Parex breathable render product, sd value and Australian availability
- Confirm current Parex/Alumasc distribution nationally
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Rockcote Breathable Render System
Breathable vapour-permeable render — exterior masonry facade
System Description
Rockcote / Saint-Gobain Weber supplies breathable render systems for exterior masonry facades where low sd value and vapour permeability are required. Confirm specific product in the Rockcote/Weber range for breathable vapour-permeable render with Saint-Gobain Weber technical. TODO: owner confirm — specific Rockcote/Weber breathable render product, sd value and TDS.
Technical Properties
- Vapour-permeable render — confirm sd value from Rockcote TDS
- Exterior masonry facades
- Apply over compatible base coat
Limitations
- TODO: owner confirm — Rockcote breathable render product, sd value and current availability
- Confirm WTA classification with Saint-Gobain Weber Australia
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of breathable vapour-permeable render systems. Confirm all product selections against the current manufacturer TDS before specifying.
| Product system | Brand | sd value | Pore volume | WTA class | Application | Primary use |
|---|---|---|---|---|---|---|
| Remmers Feinputz SP | Remmers Australia | Confirm <0.14m from TDS | Confirm >35% from TDS | WTA-classified (confirm AU status) | Over Remmers base coat and primer | Breathable finish render on salt-affected and heritage facades |
| Parex Breathable Render System | Parex / Alumasc | Confirm with Parex/Alumasc TDS | Confirm with Parex TDS | TODO: confirm with Parex/Alumasc | Over compatible Parex primer and base coat | Breathable render on exterior masonry and heritage facades |
| Rockcote Breathable Render System | Rockcote / Saint-Gobain Weber | Confirm with Rockcote TDS | Confirm with Rockcote TDS | TODO: confirm with Rockcote | Over compatible Rockcote base coat | Breathable render on coastal and heritage exterior masonry |
Do not confuse breathable vapour-permeable render with:
- Standard PM render — low vapour permeability; standard polymer-modified renders have higher sd values and lower pore volumes that can trap moisture vapour behind the render surface
- Salt-resistant renovating render — different sd value and pore structure specification; salt-resistant renovating render prioritises salt crystallisation accommodation, not primarily vapour permeability
- Waterproof coatings — barrier coatings that are the opposite intent to breathable renders; applying a waterproof coating over a breathable render defeats the vapour permeability of the system
- Elastomeric crack-bridging coatings — applied over render as a topcoat; applying these over breathable render reduces the system sd value and can trap moisture vapour
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 classification, AS 3700, NCC requirements, and applicator warranty conditions. Products marked TODO: owner confirm require verification before specifying. Do not rely on this reference as a substitute for professional engineering or facade consultant advice.