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Passive Purple (VCL) and FRED (Intumescent Paint) - VCL and Fire-Rated B Liquid Applied Membrane - Air Vapour and Fire-Retardant Coating

Verified by manufacturer 3 days ago

Intelligent Membranes Product certifications:
  • Reaction to Fire Classification

    Certificate type

A combined fire-retardant and airtight vapour control coating.

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Application

PRODUCT APPLICATION – PASSIVE PURPLE + FRED SYSTEM PREPARATION

  • Substrates to be clean, dry, frost-free and free from dust, oil, grease, release agents and laitance.
  • Remove loose or friable material.
  • Fill voids, gaps and cracks before application.
  • Moisture content of timber substrates is to be within the manufacturer’s acceptable limits.
  • Prime porous or friable substrates where required in accordance with the manufacturer’s written instructions.

APPLICATION – AIRTIGHT VAPOUR CONTROL LAYER

Product:

Passive Purple

Method:

  • Apply by airless spray or roller.
  • Ensure even, continuous coverage forming a fully bonded airtight membrane.
  • Apply to achieve the manufacturer’s specified wet film thickness (WFT) and dry film thickness (DFT).

Continuity:

  • Extend membrane across junctions, interfaces, service penetrations and structural connections.
  • Ensure airtight sealing around windows, doors, floor zones, roof junctions and service openings.
  • Reinforce high-movement areas where required to maintain membrane integrity.

Drying Time:

Allow the membrane to dry fully before overcoating with a fire-retardant layer. Drying times subject to temperature, humidity and site ventilation conditions.

540 APPLICATION – FIRE RETARDANT LAYER

Product:

FRED

Method:

  • Apply by airless spray or roller over fully cured Passive Purple layer.
  • Apply the manufacturer’s specified coverage rate to achieve the required fire classification.
  • Ensure uniform and continuous thickness to maintain the tested fire performance.

Performance requirement:

Application must achieve system classification to EN 13501-1 Class B-s1,d0 when installed as tested.

Where incorporated within tested wall or ceiling assemblies, the system may contribute up to 25 minutes of additional fire resistance, subject to substrate type and approved build-up.

ENVIRONMENTAL CONDITIONS

  • Do not apply below the manufacturer’s minimum temperature recommendations.
  • Protect from rain, frost and condensation during application and curing.
  • Ensure adequate ventilation during drying and curing periods.

PROTECTION

  • Protect completed work from mechanical damage prior to covering or lining.
  • Inspect membrane continuity and coating thickness prior to installation of internal linings or external finishes.

Description

Passive Purple + FRED

Fire-Retardant Airtight Vapour Control System

Passive Purple and FRED, when combined, form a high-performance, fire-retardant airtight vapour control system engineered for projects requiring enhanced fire resistance, airtightness, and advanced moisture management.

This integrated system is designed for both new build and retrofit applications where regulatory compliance, Passivhaus-level airtightness, and improved fire performance are critical. The fully bonded liquid-applied membrane creates a continuous, airtight layer while enhancing the substrate's fire resistance.

The combined system achieves fire Class B-s1,d0 classification in accordance with EN 13501-1, providing superior surface spread of flame performance and smoke control characteristics.

When specified as part of a tested build-up, the system can contribute up to an additional 25 minutes of fire performance, depending on substrate type and construction assembly. This makes it particularly suitable for timber frame, retrofit upgrades, and projects requiring enhanced compartmentation performance.

As a water-based, VOC-free solution, the system supports healthy indoor air quality and sustainable construction practices. It is suitable for application via airless spray or roller, ensuring efficient installation across a wide range of substrates.

Features and benefits:

  • Fire Class B-s1,d0 certified to EN 13501-1 when used together.
  • Can contribute up to 25 minutes of additional fire performance (subject to tested assembly).
  • Intumescent fire-retardant properties.
  • Airtight vapour control layer – Passivhaus certified performance.
  • Reduces uncontrolled air leakage to improve energy efficiency.
  • VOC-free, water-based formulation.
  • Airless spray or roller application.
  • Strong adhesion to masonry, timber, OSB, plasterboard, concrete and mixed substrates.
  • Suitable for new build and retrofit projects.
  • Resistant to radon gas and elevated temperatures.
  • Supports Net Zero and low-carbon construction strategies.

General information

Color

Purple

Orange

Finish

Coated

Material

Acrylic

Polymer

Shape

Formless

Length

Bespoke

Width

Bespoke

Height

Bespoke

Warranty description

Other

Uniclass

Pr_35_31_68_29 Flame-retardant coatingsPrimary
Pr_25_57_65_60 Plastics sheets

CAWS

G10/650 Site painting

J41/395 Air and vapour control layer

H31/261 Air and vapour control membrane

P10/60 Air and vapour control layer

H30/261 Air and vapour control membrane

M60/19 Flame-retardant coatings

M60/18 Special coating

H30/30 Air and vapour control membrane

M60/195 Special coating

M60/175 Protective coating

M22/120 Sprayed

P10/310 Air and vapour control layer

M60/172 Flame-retardant coating system

SKU Code

IM/00PP11.4, IM/00FRED10

Specification data - Flame-retardant coatings

Classification data

Solvent

Water.

VOC content (maximum)

VOC free.

Opacity

Opaque.

Colour

Orange.

Finish

Matt.

Reaction to fire

To EN 13501-1, Class B-s1,d0.

Consumption (per layer applied)

0.3 kg/m² (Passive Purple).
0.5 kg/m² (FRED).

Density

1200 kg/m³ (Passive Purple).
1350 kg/m³ (FRED).

Drying time

4–24 hours.

Storage

Two years at 5–20°C (Passive Purple).
One year at 5–20°C (FRED).

Colour

Purple (Passive Purple).
Orange (FRED).

Sustainability data

Country of material origin

United Kingdom

Country of product manufacture

United Kingdom

Material

Acrylic
Polymer

Product certifications

Reaction to Fire Classification

Reaction to Fire Classification

Passive Purple & FRED - Reaction To Fire Classification Report

Literature

Passive Purple  FRED install guide

Passive Purple FRED install guide

Passive purple and FRED product sheet

Passive purple and FRED product sheet

Fred - Safety Data Sheet

Fred - Safety Data Sheet

Passive Purple - Safety Data Sheet

Passive Purple - Safety Data Sheet

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