Passive Purple Brush – Detail & Joint Airtight Membrane - Brush-applied Liquid Airtight Membrane
Verified by manufacturer 1 month ago
Intelligent airtight vapour control membrane (AVCM) with fibre-reinforced polymer emulsion for enhanced gap-spanning capability. Brush-applied for sealing of junctions and service penetrations.
Application
Product Applications
- Floor-to-wall airtight connections for vapour control
- Wall-to-ceiling airtight junctions to prevent air leakage
- Window-to-wall airtight sealing for energy efficiency
- Pipe and service penetration sealing for airtightness and vapour protection
- Airtight wall coating for vapour control and moisture protection
- Wall-to-wall airtight joints for continuous building envelope protection
- Vertical and horizontal airtight joints for air and vapour control membranes
- Curtain wall airtightness detailing for thermal performance
- Wall-to-roof airtight sealing, including steel deck vapour control connections
Description
BBA and Passivhaus certified, Passive Purple Brush is a fibre-reinforced, brush-applied airtight vapour control membrane (AVCM) designed for sealing junctions, service penetrations, and hard-to-reach areas where traditional tapes and membranes fail. Applied straight from the tub, it bonds to a wide range of substrates—including brick, concrete, timber, PVC, aluminium, and polyurethane foam—and provides a flexible, long-lasting seal that moves with the building to prevent cracks and air leaks.
Key Features & Benefits
- Brush-applied precision – ideal for corners, reveals, and junctions.
- Fibre-reinforced – bridges larger gaps and maintains flexibility.
- Vapour control – airtight but breathable, helping prevent mould and damp.
- Multi-surface adhesion – proven performance on mixed substrates.
- Retrofit & new build ready – perfect for Passivhaus, EnerPHit, and low-energy projects.
- VOC-free – safe for indoor use and environmentally friendly.
- Weather-tolerant – can be applied to slightly damp surfaces.
Applications
- Wall-to-ceiling and wall-to-floor junctions
- Around window and door frames
- Joist ends and beam penetrations
- Service penetrations for pipes, cables, and ducts
- Substrate changes where cracking is likely
Performance
- Achieves airtightness levels up to 0.03 ACH (20x better than Passivhaus standard)
- 45% elongation – maintains seal during building movement
- Excellent adhesion across varied materials
General information
Color | Purple White Other Green Blue |
Finish | Other |
Material | Polymer |
Shape | Formless |
Length | Bespoke |
Width | Bespoke |
Height | Bespoke |
Warranty description | Lifetime |
Uniclass | |
CAWS | P10/60 Air and vapour control layer P10/310 Air and vapour control layer |
SKU Code | IM/00PPB6/9 |
Product range |
Specification data - Plastics sheets
Classification data | |
Product reference | Passive Purple Brush: Precision Airtight Membrane for Effective Sealing and Detailing. |
Material | Water-based polymer. |
Purpose | Airtight vapour control membrane. |
Standard | To EN ISO 12572, BS EN 12114, BS EN ISO 11925-2 and BS EN ISO 4624. |
Third-party certification | British Board of Agrément (BBA), EOTA TR008 and PASSIVHAUS certified. |
Performance characteristics | |
Tensile strength (minimum) | 42 N/50 mm². Flatwise tensile strength to ASTM C0297-16, all substrates met ICC-ES AC212 criteria for acceptance. Manufacturer guidanceFlatwise tensile strength. |
Tear resistance | To EOTA TR008, Pass. |
Elongation to break | 264% (average value) and to BS EN ISO 527-3, 262.7% (average value after ageing). |
Resistant to underground gases | Manufacturer guidanceConsult manufacturer for more details and insert requirements. |
Water vapour resistance (minimum) | µ-value to ISO 12572, 35 967. SD-value to ISO 12572, 11.5 (at 0.32 mm dry thickness) and 17.3 (at 0.48 mm dry thickness). Manufacturer guidanceTo EN ISO 12572, μ = 35967. |
Fire performance | To EN 13501-1, Class C. Flame propagation fire reaction to EN ISO 11925, Pass. |
UV stabilization | Manufacturer guidanceConsult manufacturer for more details and insert requirements. |
Environmental performance requirements | |
Environmental rating | Class M1. |
Volatile organic compounds (VOC) emissions level (maximum) | To EN ISO 16000-9/ 6, EN 717-1 and EN 180 16000-28, free from VOC. |
Recycled contentAs defined in clause 7.8 of BS EN ISO 14021 | 0%. Guidance for specification option: Grinded as solid film in plastics. |
Form | Liquid. |
Root inhibitor | Manufacturer guidanceConsult manufacturer for more details and insert requirements. |
Physical properties | |
Colour | Purple. White. Blue. Green. Orange. Manufacturer guidancePassive Purple Brush and Passive Purple Brush Editions can be made into other colours on demand. Consult manufacturer for more details and insert requirements. |
Weight (minimum) | 1.15 kg/L. Manufacturer guidanceDensity. |
Drying time | 4–48 hours. Guidance for specification option: Indicative drying time. Depending on substrate temperature, air humidity etc. |
Air tightness | 0.04 m³/h·m². Guidance for specification option: Airtightness floor/ wall after ageing (NBN EN 12114 Eurocode 7):. (50 bar) (v). |
Adhesion | Adhesion on red brick (dry or moist): to ISO 4624, >1 N/mm². Adhesion on concrete brick (dry or moist): to ISO 4624, >1 N/mm². Adhesion on PVC: to ISO 4624 0.8 N/mm². Adhesion to aluminium: >1 N/mm². Adhesion on ethylene propylene diene monomer (EPDM): >1 N/mm². Adhesion on calcium silicate stone (dry or moist): to ISO 4624, adhesion value exceeding substrate strength. Adhesion on roofing: adhesion value exceeding substrate strength. Adhesion of spray plaster on Passive Purple Brush: adhesion value exceeding substrate strength. Guidance for specification option: Adhesion on EPDM (Tridex): >1 N/mm². Adhesion of spray plaster (Knauf MP75) on Passive Purple Brush: adhesion value exceeding substrate strength. |
Water penetration | To ASTM E331, all substrate meet ICC-ES AC212 criteria for acceptance. Manufacturer guidanceWater spray/ rain penetration. |
Dangerous substances | To EN ISO 16000-9/ 6, EN 717-1 and EN 180 16000-28, free from carcinogenics, ammonia and formaldehyde. |
Consumption (per layer applied) | 0-5–1 kg/m². Guidance for specification option: Total advised indicative consumption. Dependent on substrate. |
Sustainability data
Contains Red List materials | No |
Country of material origin | Europe |
Country of product manufacture | Europe |
Material | Polymer |
Recyclability | Not recyclable due to its adhesion to other products |
Recycled contentAs defined in clause 7.8 of BS EN ISO 14021 | 0 % Guidance for specification option: Grinded as solid film in plastics. |
BIM objects
| Platform | Compatible | Version |
|---|---|---|
 Revit | - | 1 |
Literature
Airtight Details
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