Repair Systems — 03 — Facade & External Envelope
Breathable and vapour-permeable render systems
Technical product reference for breathable and vapour-permeable render systems — WTA-compliant renders with low sd value and high pore volume allowing moisture vapour to escape from the facade substrate without disrupting the render surface.
What are breathable/vapour-permeable renders?
Breathable and vapour-permeable renders are render systems with a high pore volume (typically >25–35%) and low vapour diffusion resistance (sd value typically <0.14m) that allow moisture vapour generated within the facade substrate to escape through the render body without causing blistering, delamination, or surface disruption. They are used on masonry facades where residual moisture in the substrate cannot be fully controlled — for example, where rising damp treatment has been applied but some moisture remains.
Product Reference
3 products — 3 brands — breathable and vapour-permeable render systems only — scroll to view all
System Description
Remmers supplies WTA-classified vapour-permeable render systems for facades where moisture vapour transmission from the substrate is critical. The specific product name should be confirmed with Remmers Australia — their range includes both renovating renders and lighter vapour-permeable exterior renders. TODO: owner confirm — Remmers exterior vapour-permeable render product name and specification for Australian market. Confirm sd value, pore volume and WTA classification with Remmers Australia technical before specifying.
Technical Properties
- WTA-classified vapour-permeable render
- High pore volume — allows moisture vapour to escape
- Low sd value — confirm from current Remmers TDS
Limitations
- TODO: owner confirm — Remmers product name for vapour-permeable exterior render in Australia
- Not suitable over substrates with active water ingress under pressure
- Confirm minimum pore volume and sd value from current TDS
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Caparol Capagrund / RenoExpert
Vapour-permeable render system for damp masonry facades
System Description
Caparol (DAW SE Australia) supplies vapour-permeable render and coating systems for moisture-affected masonry facades. TODO: owner confirm — Caparol vapour-permeable render product name and availability in Australia. Caparol is a major European manufacturer of breathable and vapour-permeable facades systems. Confirm current Australian product range, sd value, pore volume and system sequence with Caparol Australia before specifying.
Technical Properties
- Vapour-permeable render for damp masonry
- High moisture vapour transmission — low sd value (confirm from TDS)
- Exterior use
Limitations
- TODO: owner confirm — Caparol vapour-permeable render product name and availability in Australia
- Confirm sd value, pore volume, and WTA classification status with Caparol Australia
- Confirm current distribution network in Australia
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
Rockcote Breathable Render
Breathable polymer-modified render — exterior facade
System Description
Rockcote (Saint-Gobain Weber) supplies polymer-modified render systems for exterior facades including renders with enhanced vapour permeability. TODO: owner confirm — confirm the current Rockcote or Weber product name and specification for breathable/vapour-permeable render application on damp or moisture-affected masonry facades. The Saint-Gobain Weber range includes various render systems with different vapour permeability ratings — confirm the sd value and pore volume of the selected product from the current TDS before specifying for moisture-critical applications.
Technical Properties
- Polymer-modified render with vapour permeability
- Pre-bagged — mixed with water
- Exterior masonry use
Limitations
- TODO: owner confirm — exact Rockcote/Weber product name for vapour-permeable render
- Confirm sd value meets project specification
- Not all Rockcote/Weber renders are equally breathable — confirm from current TDS
PROCUREMENT SOURCES
Confirm suitability with the current manufacturer TDS before specifying or applying.
System Comparison
Side-by-side comparison of breathable and vapour-permeable render systems. Confirm all product selections against the current manufacturer TDS before specifying.
| Product | Brand | Sd value | Pore volume | WTA class | Exterior | Primary use |
|---|---|---|---|---|---|---|
| Remmers Außenputz WTA | Remmers | Confirm from current Remmers TDS | WTA minimum — confirm with Remmers AU | WTA-classified — confirm with Remmers AU | Yes — exterior masonry | Damp masonry facades where moisture vapour transmission is critical |
| Caparol Capagrund / RenoExpert | Caparol / DAW SE | Confirm from TDS with Caparol AU | Confirm from TDS with Caparol AU | TODO: confirm WTA status with Caparol AU | Yes — exterior use | Moisture-affected damp masonry facades — European specialist product |
| Rockcote Breathable Render | Rockcote / Saint-Gobain Weber | Confirm from TDS with Rockcote AU | Confirm from TDS with Weber AU | TODO: confirm WTA status with Weber AU | Yes — exterior masonry | Exterior masonry facades requiring vapour-permeable render |
Do not confuse breathable/vapour-permeable renders with:
- Salt-resistant renovating render (WTA sanierputz) — a more specific subset with both breathability AND controlled salt resistance — listed on the salt-resistant render page
- Elastomeric crack-bridging coatings — topcoat coatings applied over render to bridge hairline cracks — vapour-permeable coatings are a separate product class
- Standard polymer-modified render — these are not formulated for high vapour permeability and will trap moisture in damp substrates
Disclaimer
This page provides general technical information only. Final product selection must be confirmed against the current manufacturer TDS, project specification, substrate condition, exposure classification, and AS requirements. Products marked TODO: owner confirm require verification before specifying. Do not rely on this reference as a substitute for professional building or facade consultant advice.