Armaflex EVO Pipe Insulation

Armaflex EVO Pipe Insulation — Class O Nitrile Rubber Foam

Armaflex EVO (AF/ArmaFlex) is the world's most specified elastomeric foam pipe insulation and the flagship product of the Armacell Armaflex range. A closed-cell nitrile rubber foam with a built-in vapour barrier, Class O fire rating and Microban® antimicrobial protection, Armaflex EVO is the professional's choice for HVAC, chilled water, heating and plumbing applications across the UK.

Available in standard (open slit, adhesive required at joints) and self seal (factory-applied adhesive closure for tool-free installation) versions, in 2m lengths and 15m coils.

Key Benefits

Class O fire rated — BS 476 Part 6 & 7, B-s2,d0 to EN 13501. Produces 50% less smoke than standard elastomeric foams
Built-in vapour barrier — μ ≥ 10,000, eliminates condensation on chilled water and cold pipework without additional wrapping
Low thermal conductivity — λ ≤ 0.033 W/mK at 0°C
Microban® antimicrobial protection — inhibits mould and mildew growth throughout the product's lifetime
Operating temperature — -50°C to +105°C
Proven 40+ year performance — confirmed by independent testing of 1980s installations

Standard vs Self Seal

Standard (open slit) — requires Armaflex 520 adhesive to close the longitudinal seam and all butt joints. Preferred by experienced installers for complex pipework with many fittings
Self Seal — factory-applied adhesive closure strip. Simply press to seal — no adhesive required for straight runs. Faster installation, ideal for straightforward pipework

Wall Thickness Selection Guide

9mm wall — Condensation control on chilled water in conditioned spaces
13mm wall — Standard for heating, hot water and chilled water. Meets Part L for most domestic applications
19mm wall — Commercial HVAC, chilled water and frost protection
25mm wall — Maximum performance for chilled water, refrigeration and exposed pipework

Shop by Pipe Size

15mm | 22mm | 28mm | 35mm | 42mm | 48mm | 54mm | 60mm | 76mm | 89mm | 114mm

Frequently Asked Questions

What is Armaflex EVO?: Armaflex EVO is the latest generation of AF/ArmaFlex, Armacell's flagship closed-cell nitrile rubber pipe insulation. It combines Class O fire performance, built-in vapour resistance and Microban antimicrobial protection in a flexible, easy-to-install tube.
Is Armaflex EVO waterproof?: Yes. The closed-cell structure with μ ≥ 10,000 water vapour resistance acts as its own vapour barrier, preventing moisture ingress and surface condensation on cold pipework.
Can Armaflex EVO be used outdoors?: Standard Armaflex EVO will degrade under prolonged UV exposure. For outdoor use, finish with Armaflex Tuffcoat UV tape or specify Armaflex HT Solar for solar thermal applications.
Does Armaflex EVO prevent condensation?: Yes — the closed-cell foam and high vapour resistance prevent moisture reaching the pipe surface, eliminating condensation drips on chilled water and cold pipework without additional vapour barriers.
What thickness do I need?: For domestic heating and hot water, 13mm wall is the standard minimum. For chilled water and commercial HVAC, 19mm or 25mm is typically specified. Call our team on 0161 775 1190 for specification advice.

Complete Your Installation

Armaflex 520 Adhesive — For butt joints, bends and fittings (essential for standard version)
Armaflex Lagging Tape — Black foam tape for finishing joints and exposed edges
Armaflex Tuffcoat Tape — UV-resistant tape for outdoor installations
Rubber & Standard Pipe Clamps — Correct pipe clamps for insulated pipework

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