The system includes a range of products suitable for integration into domestic buildings. Applications include single flats, multiple occupancy dwellings and large luxury homes.


Radial ductwork system which simplifies mechanical extract ventilation (MEV) and mechanical ventilation heat recovery (MVHR) installation and meets the demands on modern ventilation systems.

All circular plenum connections are supplied with gaskets as used on Lindab Safe systems, which fulfils the toughest demands for airtightness. This ensures the ducting can be interconnected quickly and easily.

All manifolds and plenum boxes have a Smart Lock function which allows Lindab’s LFPE semi-flexible duct to be attached with a simple push and click, and can be removed quickly and simply without the need for tools, and with no damage to either the flexible duct or the plenum/ manifold.

Features and benefits:

  • Radial system: The radial principle involves individual ducting tubes from each extraction and supply point to plenum and distribution boxes connected to the mechanical unit. This eliminates cross-contamination and noise transfer.
  • Semi-rigid ducting: Requiring only the minimum of space, ducting can be run in voids without interference to other services or structural members.
  • Reduced power use: Lindab semi-rigid duct takes a swept bend form around corners and has a smooth internal surface which reduces pressure drops and power consumption.
  • Energy-efficient: Supply and extract points feed directly from central distribution boxes, significantly reducing system pressure drops and power loss which maximises fan power efficiency.
  • Airtightness: Components fulfil the requirements of air tightness class D, Lindab Safe connections on circular plenums have built-in double lipped gaskets and are Eurovent certified.
  • Easy installation: Push and click Smart Lock enables simple installation without the need for specialist tools. Installation time can be reduced by up to 66% compared to traditional ducting methods (no sealant or tape required). Ducting can also be removed easily if required.
  • Fire protection: Intumescent fire sleeves and collars offer fire protection, thus avoiding the need to construct fire resistant ducts.
  • Noise sensitivity: Provides acoustic separation, eliminating cross-talk sound transfer between rooms. Silencers are optionally available to reduce noise levels/ sensitivity. The system includes dampers, silences, valves and grilles.
  • Enhanced aesthetics: Lindab Airy high-performance air valves offer improved appearance for harmonised integration with interior design.
  • Compliance: Complies with building regulation guidelines and is SAP Appendix Q listed, which simplifies a buildings energy consumption calculations.
  • The semi-rigid polyethene (PE) ducting is anti-static and antibacterial, with a corrugated outer surface to reduce pressure drops at corners, and has a smooth inner surface to reduce air resistance.


The system includes a range of products suitable for integration into domestic buildings. Applications include single flats, multiple occupancy dwellings and large luxury homes.

General information

Uniclass 2015

Pr_65_65_25_13 Circular plastics ductwork and fittingsPrimary


U90/150 Whole house mechanical ventilation

U90/18 Whole house mechanical ventilation

U90/420 Flexible ductwork and fittings

U90/45 Flexible ductwork and fittings

Specification data - Circular plastics ductwork and fittings

Product Reference




Semi-rigid duct.

Manifold box





Plenum box







Not required

ABA air brick adapters

AIRYB and AIRYFP supply and exhaust air valve

See 'Option' and insert requirements.

BU90 bend

DW25N insulation wrap

FIKS clamping bracket

JSU exhaust valve

KI valve - air supply NPU coupling

RCFU transition piece

SKG sliding damper

TT400 LFPE insulation

VPAB air brick fascia

Available in brown, Cotswold stone, white and terracotta, insert requirements.

KSU exhaust valve, White RAL 9003 KSU exhaust valve, White RAL 9010 GC external wall grille

Standard product features

Technical characteristics:

Consult technical literature for details on individual products and their performance.

Product Options

Product properties:

Consult manufacturer's literature and insert dimension requirements.


- AIRYB (valve body) supply and exhaust air valve:

The product is available in the following nominal diameters:

  • 63 mm.
  • 125 mm.
  • 250 mm.
  • 500 mm.
  • 1000 mm.
  • 2000 mm.
  • 4000 mm.
  • 8000 mm.

The flat front plate (AIRYFP) is available in 100, 125 and 160 mm diameter.

Available in five standard front plate shapes:

  • ROUN – a circle.
  • BOW – a square with slightly bulged edges,
  • SQUA – a square.
  • ELLI – an ellipse.
  • RECT – a rectangle.

Available in White RAL 9003 and RAL 9010, gloss 30.