Twiga Insul Duct Wrap

TWIGA Insul Duct Wrap Ductwrap, a light weight thermal insulation blanket having long product life is specifically designed to wrap around air conditioning ducts. Manufactured from fine, stable and uniformly textured non combustible inorganic glass fibers bonded together by a non water soluble and fire retardant binder.

Features & Benefits

Higher thermal resistance (R Value)

Minimising the loss of heat from the working fluid to the surrounding space will save energy and cost - provide uniform temperature of the supply air. It is noticeable that the efficiency of an insulation material directly depends on the thermal resistance(R - Value).

More thermal resistance less heat loss & gain inside the duct. To achieve higher thermal resistance (R-Value) is required more thickness of insulation material, if thermal conductivity of the insulation material is approximate same in same unit and mean temperature.

Thermal Resistance “R” Value

  • R = L K
  • Where 'L' = Thickness of Insulation material (m)
  • 'K' = Thermal Conductivity (W/m ºC)
  • “R” = m2 ºC/W or hr.ft2. ºF /Btu
  • R-Value is a measure of the resistance to heat flow of a material of any given thickness

Non Combustible

Prevent fire risks from the content of the services and protecting HVAC equipment from external fire damage.

High noise attenuation properties

Offers exceptional actoustic properties and enhances indoor environmental quality by absorption of mechanical noise generated by air conditioning equipment.

Condensation control

appropriate thickness of Insulation as per ambient temperature & relative humidity is used. The moisture carrying capacity of the air is related to its temperature.

When moist warm air comes into contact with cold surfaces eg. Pipe and ducts, the air is cooled and will produce precipitation on the cold surface.

Health issues/quality of indoor air

Fiberglass wool has no health hazard in any normal conditions. International Agency for Research on Cancer (IARC) monographs /WHO report (2002) explicitly states that glass wool is not carcinogenic to humans.


TWIGA Insul Duct wrap is available with a wide range of factory applied facings, FSK, Tough Guard, and Black Woven Glass Cloth & FGT.

Thermal Properties

Significantly reduces heat gain & losses.

Fire Properties

Non Combustible tested as per BS 476 part 4 and ISO 1182, IS 3808 & IMO (FTP)


  • Odorless, inert and fully compatible with all standard building material components
  • Does not encourage growth of fungi & vermin.
  • Non Hygroscopic

Tools needed for Installation

Tape Measure, sharp knife/blade, straight edge & strapping equipment

Installation Guidelines

The duct should be covered with two coats of cold applied bitumen/CPRX or any other equivalent approved product after cleaning the surface & sealing all joints against leakages.

The insulation of specific R-value and thickness should then be cut to appropriate length and stuck to the duct while the adhesive is still wet.

All longitudinal joints and circular overlaps should be sealed with aluminium foil tape (50mm width) to make the installation leak proof. For large ducts, where adhesive pins have been used, speed washers/clips should be covered completely with Aluminium foil- tape to have an air-tight finish.

The insulation should then be secured over the duct using mechanically fastened nylon/steel straps (12mm/50mm) at appropriate intervals (max 1.2m).

For ducts having width greater than 0.6m, heavy duty self- pins are to be applied to the duct at appropriate intervals (max 300mm)

Handling & Storage

Store product undercover and in dry conditions. Store flat. Handle with care, especially on the edges and corners, which can be damaged if subject to sharp or heavy impact.

Architectural Specification

Insulation material for Duct Wrap shall be lightweight blanket of non combustible Bonded Fiber Glass Wool Insulation - Supply Duct- having thermal resistance R 1.4 (24KG/m3-50 mm), Return Duct - R 0.6 (24kg/m3-25mm) suitably factory laminated with appropriate vapour barriers as per the ECBC/ASHRAE standards.