NBS Source
I'm a manufacturer

Passive Purple External: Ultimate Class B Fire Rated Internal & External Airtight Waterproof Membrane - Spray Applied Liquid Facade Membrane

Verified by manufacturer 4 days ago

PASSIVE PURPLE® EXTERNAL

Intelligent Membranes Product certifications:
  • Passive House Institute - Certificate

    Passive House Institute - Certificate

    Certificate type

  • REACTION TO FIRE - CLASSIFICATION REPORT EUI-22-000041

    REACTION TO FIRE - CLASSIFICATION REPORT EUI-22-000041

    Certificate type

  • KIWA BDA

    KIWA BDA

    Certificate type

Airtight, liquid-applied façade waterproof membrane. Vapour-open yet watertight, achieving 0.03 airtightness. Applied by spray, roller or brush as a high-performance vapour control layer.

Jump to:
BOS
+44 (0)1223 208174 Website

Application

Product Application – Passive Purple External

Passive Purple External is applied in two coats using either an airless spray or paint roller. Once cured, it forms a flexible, watertight membrane that is vapour-open and highly durable. The product is currently undergoing Passivhaus and KIWA certification.

The membrane provides:

  • A waterproof, vapour-open barrier to reduce uncontrolled air infiltration
  • Reaction to fire classification B-s1, d0 in accordance with EN 13501-1:2018
  • VOC-free formulation for a safe, eco-friendly application

Directions for Use

  1. Surface Preparation
    • Remove salt efflorescence, dust, loose material, and standing water.
    • Ensure application is on a closed surface; fill holes and joints with a fast-setting cement-based product or polyurethane foam if required.
  2. Application Conditions
    • Apply only when substrate and ambient temperature is above 5°C.
    • Application on humid surfaces is permitted, but remove any standing water.
  3. Application Method
    • Apply Passive Purple External with an airless paint spray device or paint roller.
    • Apply two coats; allow the first coat to fully dry before applying the second.
    • The product is supplied ready to use — no dilution required.
  4. Aftercare
    • Clean all tools immediately with water after use.
    • Once cured, the coating provides long-term, seamless protection.

Key Benefits During Application

  • Quick and simple installation with standard spraying or rolling equipment
  • No VOCs – safe to apply in sensitive environments
  • Seamless finish with excellent adhesion to multiple substrates

Description

Discover Passive Purple External: The Ultimate Net Zero & Passivhaus Waterproofing Solution

Introducing Passive Purple External, a revolutionary liquid-applied membrane from Intelligent Membranes. Specifically engineered to deliver superior airtightness, waterproofing, and energy efficiency, it is suitable for any construction type — from new builds to retrofits and even sensitive heritage restorations.

Why Choose Passive Purple External?

  • Unmatched Airtightness & Waterproofing – Creates a seamless, watertight barrier against rain, wind, and environmental exposure.
  • Energy Efficiency – Reduces heat loss while remaining vapour-open, preventing condensation and ensuring a healthy indoor climate.
  • Fire Class B Rated & UV Resistant – Certified performance that withstands harsh conditions for long-lasting protection.
  • Ideal for Heritage Projects – Breathable and flexible to protect and preserve historic structures.
  • Self-Cleaning & Anti-Fungal – Reduces dirt pickup, resists mould growth, and maintains a clean, durable finish.

Key Technical Characteristics

  • Raintight yet vapour-breathable
  • Crack-bridging capability
  • Carbonatation and salt protection for concrete
  • Smoke-tight and anti-carbonatation on cementitious surfaces
  • Radon and methane resistance

Applications

Passive Purple External is the go-to solution for:

  • New build airtightness – robust vapour control membranes for modern projects
  • Retrofit airtightness – eco-friendly membranes for improved fabric performance
  • Commercial & Domestic projects – reliable protection for walls, roofs, and floors
  • Heritage restoration – breathable, seamless protection without damaging original substrates

Certified Protection Against:

  • Air leakage & moisture ingress
  • Radon and methane
  • Condensation and mould
  • Weathering and UV exposure
  • Structural carbonation and salts

Backed by KIWA certification, Passive Purple External is the ideal choice for architects, contractors, and developers striving to meet Passivhaus and Net Zero standards.

General information

Color

Manufacturer guidance

Other colours are available upon request. Consult manufacturer for details.

Finish

Other

Material

Polymer

Shape

Other

Formless

Length

Bespoke

Width

Bespoke

Height

Bespoke

Warranty description

25 year

Uniclass

Pr_25_57_65_60 Plastics sheetsPrimary

CAWS

H30/261 Air and vapour control membrane

H31/261 Air and vapour control membrane

P10/60 Air and vapour control layer

H31/45 Air and vapour control membrane

P10/310 Air and vapour control layer

H30/30 Air and vapour control membrane

SKU Code

IM/00PPE10

Product range

Weatherproofing
Façade Membrane - Retrofit internal Air Barrier
Methane and Radon Barrier
Vapour Control - Air barrier / External

Specification data - Plastics sheets

Classification data

Product reference

Passive Purple External: Ultimate Class B Fire Rated Internal & External Airtight Waterproof Membrane.

Material

Acrylate polymer.

Purpose

Airtight weatherproof membrane.

Standard

To BS EN 16302, BS EN ISO 12572 and BS EN ISO 4624.

Third-party certification

Kiwa, Passivhaus certified.

Manufacturer guidance

Manufacturer's standard. SHR, BBR.

Performance characteristics

-

Tensile strength (minimum)

38/ 35 N/50mm (after ageing).

Tear resistance

To NBN EN ISO 12311, 38/ 35 N/50mm.

Elongation to break

To NBN EN ISO 12311-1, >40%.

Manufacturer guidance

Elongation after ageing.

Resistant to underground gases

Methane.
To BS EN 1062 CO₂ permeability Method A, Class C1.

Water vapour resistance (minimum)

3.1 MN·s/g.
μ-value to EN ISO 12572, 2486.
SD-value to EN ISO 12572, 0.6–1.

Guidance for specification option:

SD-value calculated value based on a consumption of 0.6–0.8 kg/m².

Fire performance

Resistance to fire class to EN13501, Class B-s1, d0.

UV stabilization

To BS EN ISO 16474-3, Pass (KIWA).

Manufacturer guidance

Consult manufacturer for certifications.

Anti-static properties

Required.

Environmental performance requirements

-

Volatile organic compounds (VOC) emissions level (maximum)

VOC free.

Recycled content

As defined in clause 7.8 of BS EN ISO 14021

0%.

Manufacturer guidance

Grinded as dry film.

Form

Liquid.

Physical properties

-

Colour

Black.
Purple.
White.
Cream.
Grey.
Blue.
Other.

Manufacturer guidance

Other colours are available upon request. Consult manufacturer for details.

Weight (minimum)

1.2 kg/L.

Manufacturer guidance

Density.

Drying time

4–12 hours.

Guidance for specification option:

In normal conditions; weather dependant.

Air tightness

To EN12114, 0.03 m³/m²·hour.

Guidance for specification option:

Airtightness system with Rockwool® panels anchored on/through Passive Purple external membrane on blockwall.

Adhesion

0.16 N/mm².
Adhesion on mineral surfaces (with use of primer as bonding): to NBN EN ISO 4624, Pass, 1 N/mm².
Adhesion of Passive Purple External on fibre cement boards (with use of primer as bonding): to NBN EN ISO 4624, Pass, 1 N/mm².
Adhesion of Passive Purple External on plywood (with use of primer as bonding): To ASTN CO297, Pass.
Adhesion of Passive Purple External on insulation boards type 'recticel': to NBN EN ISO 4624, Pass.

pH

9–10.

Solids

>50%.

Crack bridging

To EN 1062-7, Pass, Class A3 (at 23°C); Pass, Class A4 (at -10°C).
To EN1504-2, Pass.

WaterImpermeability

To EN 1062-3, W <0.1 kg/m²·h⁰·⁵.
To NBN EN 16302, Pass, 0.004 mL/cm².
Water damp permeability to EN ISO 12572, 0.75 kg/m².

Water vapour transmission

To ASTM E96, SD-value <1.0.

Temperature resistance

-20°C to + 70°C.

Application temperature

<5°C.

Consumption (per layer applied)

0.75 kg/m².

Guidance for specification option:

For a layer of 0.625 mm thick.

Manufacturer guidance

Total indicative consumption.

Sustainability data

Contains Red List materials

No

Country of material origin

Europe

Country of product manufacture

Europe

Manufacturing plant location

Material

Polymer

Recyclability

Not recyclable due to its adhesion to other products

Recycled content

As defined in clause 7.8 of BS EN ISO 14021

0 %

Guidance for specification option:

Grinded as dry film.

Expected Life

60 year

BIM objects

BOS

NBS BIM Object Standard

This BIM object has been authored to meet the requirements of the NBS BIM Object Standard.

Find out more about the NBS BIM Object Standard.

Platform Compatible Version
Revit
-

1

IFC
-

1

Product certifications

Passive House Institute - Certificate

Passive House Institute - Certificate

Passivhaus Institut Certificate

REACTION TO FIRE - CLASSIFICATION REPORT EUI-22-000041

REACTION TO FIRE - CLASSIFICATION REPORT EUI-22-000041

Pavus Fire Class B Certificate

KIWA BDA

KIWA BDA

KIWA Agrement

Literature

Passive Purple External - Product Sheet

Passive Purple External - Product Sheet

Detail drawings. Insulated concrete frame.

Detail drawings. Insulated concrete frame.

Detail drawings. Floor (Ground & intermediate)

Detail drawings. Floor (Ground & intermediate)

Detail drawings. Roof eaves parapet.

Detail drawings. Roof eaves parapet.

Detail drawings. SIPS.

Detail drawings. SIPS.

Detail drawings. Steel frame.

Detail drawings. Steel frame.

Detail drawings. Timber I beam.

Detail drawings. Timber I beam.

Detail drawings. Windows & doors

Detail drawings. Windows & doors

3D Drawings of Intelligent Membranes

3D Drawings of Intelligent Membranes

2D Drawings

2D Drawings

Case studies

"How Passive Purple External Protects Bridges and Tunnels for Decades"

"How Passive Purple External Protects Bridges and Tunnels for Decades"

Similar products from Intelligent Membranes

Airtight White Brush: High-Performance Airtight Membrane for Internal Vapour Control - Brush-applied Liquid Airtight Membrane

Airtight White Brush: High-Performance Airtight Membrane for Internal Vapour Control - Brush-applied Liquid Airtight Membrane

Airtight White: High-Performance -Fire Rated -Airtight & Vapour Control Membrane for Internal Applications - Spray-applied Airtight Liquid Membrane

Airtight White: High-Performance -Fire Rated -Airtight & Vapour Control Membrane for Internal Applications - Spray-applied Airtight Liquid Membrane

Passive Purple Brush – Detail & Joint Airtight Membrane - Brush-applied Liquid Airtight Membrane

Passive Purple Brush – Detail & Joint Airtight Membrane - Brush-applied Liquid Airtight Membrane

Passive Purple External Brush: Precise Airtight & Waterproof Sealing for Every Detail - Brush Applied Airtight Facade Membrane

Passive Purple External Brush: Precise Airtight & Waterproof Sealing for Every Detail - Brush Applied Airtight Facade Membrane

PASSIVE PURPLE® Fire rated Intelligent Airtight Vapour Control for Energy-Efficient Building Solutions - Spray-applied Liquid Airtight Membrane

PASSIVE PURPLE® Fire rated Intelligent Airtight Vapour Control for Energy-Efficient Building Solutions - Spray-applied Liquid Airtight Membrane

Waterproof Blue: High-Performance DPM for Ultimate Moisture Protection and Waterproofing - Waterproof Flexible Membrane

Waterproof Blue: High-Performance DPM for Ultimate Moisture Protection and Waterproofing - Waterproof Flexible Membrane