Custom Audio Designs Ltd

Acoustic Lagging | Duct Insulation | Pipe Insulation | Acoustic Duct Wrapping

tecsound acoustic pipe laggingacoustic pipe wrapacoustic wrap for pipessoil pipe soundproofingacoustic lagging

FT 55 AL High Performance Acoustic HVAC Insulation

Acoustic Duct Lagging 


FT 55 AL (Part Code A210) is a soundproofing complex made up of a porous felt mat and our high performance 5kg/m² synthetic acoustic membrane, faced with reinforced aluminium foil.


  • Increases acoustic insulation of the duct element to which it is applied, basing its effect on the presence of an absorbent element and a high elasticity and high density insulating membrane.
  • Tested to BS EN 14366:2004
  • Flexible.
  • Easy handling and adaptable to uneven surfaces.
  • Cold- and heat-resistance.
  • Excellent ageing resistance.
  • On surfaces in good condition, installation can be corrected without loss of adhesiveness
  • Acoustic Duct LaggingMade using 100% recycled felt.
Density (membrane)1.9g/m³
Pliability (UEAtc)Does not break when bent at -10°C
Tensile Strength (UNE 104-281/6.6)>30 N/cm² (Membrane)
Elongation (UNE 104-281/6.6)300%
Thermal Conductivity Coefficient0.037 W/m°C (felt)

Typekg/m²Thickness (mm)Packaging
FT 55 AL5.512.65.5 x 1.2m rolls

Instructions for use:

  • Soundproofing of PVC sewage ducts in building.
  • Soundproofing of air conditioning ducts.
  • Soundproofing of industrial pipes.


Installation: Measure the development of the duct to be soundproofed, adding 5 cm for overlaps. Use scissors to cut the required quantity of FT 55 AL, crosswise. Wrap tie duct in such a way that the textile felt is, as much as possible, in contact with the surface, starting at the lower part of the pipe. Use a plastic flange for anchoring, every 20 cm. To seal the overlaps, an aluminium adhesive tape is used. It is important that the joints are perfectly sealed to prevent diminishing of the insulation. Usually the treated pipe is boxed in with double plasterboard to finish.

This product is also extremely useful as an underlay inside vehicles to reduce road noise. It should be applied with the foil side facing upwards and felt side facing down to the chassis.


The substrate must be free from materials which can damage the product both during and once applied, such as, mortar remains, etc.


Acoustic Duct Lagging 

RW25 dB

Noise caused by the discharge of fluids in drainpipes is one of the commonest problems in residential and office buildings, due to low acoustic insulation provided by standard pipes built into walls and false ceilings.

In one single product FT 55 AL gives you an absorbent material and a heavy layer insulating membrane, with the characteristics needed to provide an answer to this problem.


Soundproofing of drainpipes and soilpipes (especially at the elbows) as well as ductwork.

 Acoustic Duct Lagging Acoustic Duct Lagging
 Acoustic Duct Lagging Acoustic Duct Lagging
 Acoustic Duct Lagging Acoustic Duct Lagging
acoustic test to BS 14366

We can supply 450mm length cable ties as an optional extra.

All information contained in these details is given in good faith but without warranty.
Custom Audio Designs reserves the right to alter the specifications of any product without notice.
©Custom Audio Designs