Insulation material for duct shall be factory laminated vapour barrier of different types eg : FSK, WMPVR R Plus, R 3035 HD etc faced resin bonded
fiberglass wool. The Thermal conductivity of the insulation material shall not exceed 0.034 W/m K at 25° C mean temperature. The thickness of insulation shall be so selected as to prevent any condensation and should be able to meet R-Value requirements.
The minimum thermal resistance (R-Values) for insulation of ducts (as per Ashrae 90.1-2004 and ECBC 2017) shall be as described below:
Supply air ducts R = 1.4 m2 deg. /W (thickness requirement for glasswool 50 mm).
Return air ducts R = 0.6 m2 deg. /W (thickness requirement for glasswool 25 mm).
The nominal density of Resin Bonded Fiberglass insulation shall be 32 kg/m3.
The minimum thickness of material used for duct thermal insulation shall be 25 mm.
The scope of this section comprises the supply and application of insulation conforming to these Specifications.
Insulation material shall be non toxic, chemically inert , non combustible, non ignitable, shall have zero ozone depletion potential, zero calorific value no heat evolution and shall be inherently proof against rotting , mould and fungal growth and attack by vermin.
The materials shall comply with following standards.
BS 476: Part 4 – non combustible (as per new NBC 2016, clause: 126.96.36.199.5 part 4 fire and life safety code).
BS 476: Part 5 – not easily ignitable (class P).
BS 476: Part 6 – fire propagation index (I<12).
BS 476: Part 7 - surface spread of flame (class 1).
The material should comply to class 'O' fire rating as per BS 476 part 6&7.
The product shall be able to work effectively at ambient temperature range of -100° C to 150° C
Insulation material for Duct Acoustic Lining shall be resin bounded fiberglass wool with one side factory laminated either Black Glass Oven Cloth or Black Glass Tissue. The Thermal conductivity of the fiberglass for air-conditioning application shall not exceed 0.034 W/m K at 25° C mean temperature and average Noise Reduction Coefficient (NRC=1, frequency range from100 Hz to 8000Hz). The density of insulation material shall be either 48 Kg/m3 and thickness of insulation material shall not less 25 mm.
The installation guideline for glasswool in Duct Acoustic Lining :
The inside duct surface should be cleaned with suitable solvents and rendered free from all physical and chemical impurities.
Fix 22 gauge G.I.channels & angle framework 25 mm wide depth equal to thickness of insulation at 600 mm centre, screwed to the sheet metal by means of brass metal screws.
Cut the panel of glasswool insulation material & fix in framed work using two coats of cold applied bitumen based adhesive.
The inner most surface of insulation material shall be covered with factory laminated either Black Glass Oven Cloth or Black Glass Tissue.
Finally cover the insulation with 0.5 mm thick perforated aluminium sheet having 20% perforation with joints overlapped and screwed to the frame by means of brass metal screws, to produce an even surface.
Twiga Acoustic Board is a high-density rigid board made of glasswool insulation. It's one side is laminated with black glass cloth for better sound absorption and aesthetic finish. The other side is laminated with aluminium foil to act as a vapour barrier.
Product name: Twiga Acoustic Board.
Thickness: 25 mm thick Rigid board.
Density: 70-80 kg/m3.
Top facing: Black glass cloth.
Bottom facing: Aluminium foil.
Size of the board: 2.5 m x 1.2 m.
Lower installed cost.
Increases room space due to lower insulation thickness.
High acoustic properties.
No perforated metal cover is required.
More area for acoustic absorption.
Easy to install, maintain and retrofit.
No fiber migration.
Vibration control at automobile crash testing pit.
Twiga Insul Preformed Pipe Sections, designed for easy and rapid “snap-on” installation are a single- piece moulded insulation made from shot free, non-combustible glass fibers bonded together with a high temperature resistant binder for pipe diameter from 20 mm NB to 300 mm NB. The section is available with / without factory laminated aluminium foil facings.
Twiga Lamella Mats are made from glassfiber wedges laminated with aluminium foil. Lamella Mats are compression resistant (maintain thickness at bends), easy to handle and are suitable for large pipes of diameter from 300 mm NB and above.
Twiga Insul Pipe Sections and Lamella Mat are suitable for the thermal and acoustic insulation:
Heating and hot water services pipe.
Steam pipes up to 230° C with bare pipe section.
BS 476 part 7- Class 1 - surface spread of flame Nil.
Chilled water and cold-water services pipe.
Features & Benefits
Green building material: low embodied energy, zero ozone depleting potential, minimum VOC.
Fire Safe: non combustible, Does not emit toxic fumes.
Excellent thermal resistance at low cost (low thermal conductivity).
Low cost: easy and fast to install.
Non corrosive to metal: no shot content / impurities.
Resistant to chemicals, oil, fungus, bacteria, rot, and vermin attack.
The Glasswool insulating material shall be applied for chilled/ hot water pipes as under.
Glasswool insulating material shall be applied for chilled/ hot water pipes as under. The rigid pre-formed moulded sections of glasswool having a uniform density of 80±15% Kg/m3 and thermal conductivity shall not be more than 0.030 W/m.K at 25° C mean temperature also shall confirm IS 9842. The material for piping insulation shall be factory laminated one side with Aluminium foil on the outside. The Aluminium foil shall extend by a minimum 50 mm on one side of thepipe section along the length to seal all longitudinal joints. Bonding of insulation material shall be with a cold setting compound.
The thickness of insulation material shall be selected as per diameter of pipes.