Armaflex Sheet Insulation

Armaflex Sheet Insulation — Class O Elastomeric Foam

Armaflex sheet insulation is the flexible, closed-cell elastomeric foam solution for insulating ductwork, tanks, vessels, flat surfaces and irregular shapes where Armaflex pipe tubes cannot be used. Manufactured by Armacell, Armaflex sheet products share the same core performance as the pipe range — Class O fire rating, built-in vapour barrier and low thermal conductivity — in a flat sheet format that can be cut, shaped and bonded to any surface.

Available in plain, self-adhesive and specialist variants, including UV-resistant Tuffcoat and high-temperature HT Solar, Armaflex sheet insulation covers the full range of HVAC, refrigeration and building services applications.

The Armaflex Sheet Range

AF/Armaflex EVO Sheet — Plain — Standard Class O closed-cell foam sheet for ductwork, tanks and vessels. Requires Armaflex 520 adhesive for bonding. Available in 9mm, 13mm, 19mm and 25mm thicknesses
AF/Armaflex EVO Sheet — Self-Adhesive — Factory-applied pressure-sensitive adhesive backing for fast installation without separate adhesive. Ideal for flat duct surfaces and tank insulation
Armaflex Duct Sheet — Dedicated duct insulation sheet with optimised thermal performance for rectangular and circular ductwork in HVAC systems
Armaflex Duct AL Sheet — Foil-faced duct insulation sheet providing a clean, professional finish on exposed ductwork with enhanced radiant heat reflection
Armaflex Duct Plus Sheet — Enhanced duct insulation sheet with improved thermal performance and surface finish. Available in self-adhesive versions for faster installation
Armaflex Tuffcoat Sheet — UV-resistant elastomeric foam sheet for outdoor ductwork, external pipework and exposed surfaces
Armaflex HT Solar Sheet — High-temperature sheet for solar thermal collectors, heat pump equipment and outdoor applications up to +150°C

Key Benefits

Class O fire rated — BS 476 Part 6 & 7, B-s2,d0 to EN 13501. Suitable for commercial buildings and HVAC installations
Built-in vapour barrier — closed-cell structure prevents condensation on chilled ductwork and cold surfaces without additional vapour barriers
Low thermal conductivity — λ ≤ 0.033 W/mK, minimising heat gain on cooling systems and heat loss on heating ductwork
Flexible and easy to cut — cuts cleanly with a sharp knife, bends around corners and curves without cracking
Microban® antimicrobial protection — built into Armaflex EVO sheet, inhibiting mould and mildew growth

Technical Specifications

Material: Closed-cell nitrile rubber (NBR) elastomeric foam
Fire classification: Class O (BS 476), B-s2,d0 (EN 13501)
Thermal conductivity: λ ≤ 0.033 W/mK at 0°C
Water vapour resistance: μ ≥ 10,000
Operating temperature: -50°C to +105°C (standard); up to +150°C (HT Solar)

Common Applications

Rectangular and circular ductwork insulation in HVAC systems
Cold water tanks, buffer vessels and thermal stores
Air handling unit (AHU) casings and plenums
Chilled water pipework and equipment insulation
Refrigeration plant and cold room pipework
Outdoor ductwork and equipment (Tuffcoat and HT Solar variants)

Complete Your Installation

Armaflex 520 Adhesive — Contact adhesive for bonding plain Armaflex sheet to ductwork and surfaces
Armaflex Cleaner — Surface preparation and adhesive cleaner for Armaflex installations
Armaflex Lagging Tape — For finishing joints and exposed edges on sheet installations
Armaflex Tuffcoat Tape — UV-resistant tape for outdoor sheet installations

For technical advice on duct insulation specification or help selecting the right sheet thickness, call our team on 0161 775 1190 (Mon–Fri 8am–4pm).