25 Sep, 2017

Duct Liner (DL)

Duct Liner


Duct Liner is a highly efficient, semi-rigid insulation composed of fine, stable and uniformly textured inorganic glass fibers bonded together by a non-water soluble and fire-retardant thermosetting and heat resistant resin. It is free from coarse fibers and shot due to its mineral composition.


Duct Liner is supplied semi-rigid and rigid faced with a strong, dimensionally stable Non-Woven Black Glass Tissue (BGT).


Duct Liner is intended for use in commercial, institutional, industrial and residential construction as thermal and acoustical insulation of heating air-conditioning and interior of dual-temperature duct work, air handling equipment and plenums operating at air-velocities up to 30 m/s (6000 FPM) and temperatures up to 121 °C (250 °F).
Also used as an efficient sound absorption treatment of walls and ceilings, acoustic enclosures, generator rooms, studios, curtain walls, auditoriums, conference rooms, theaters and others.

Installation Recommendation

Duct Liner Blankets are available in rolls. The desired application length can be easily measured and cut from the full roll. Duct Liner is applied to the interior of ducts and plenums with the black surface facing the air stream. Transverse joints are to be neatly butted, with no interruptions or gaps. Longitudinal corner joints are to be overlapped and compressed.

Duct Liner should be adhered to sheet metal ducts with 100% coverage of adhesive, and all exposed leading edges and all traverse joints coated with adhesive. The adhesive shall conform to standard ASC-A7001C-1972 or as approved by the project consultant. The liner should be additionally secured with mechanical fasteners which will compress the product sufficiently to hold it firmly in place.

For velocities to 10 m/s: fasteners should start within 75 mm of the upstream transverse edges of the liner and 75 mm from longitudinal joints, and should be spaced at maximum of 300 mm on centers around the perimeter of the duct, except the they may be maximum of 300 mm from a corner break.

For velocities from 10 to 20 m/s: fasteners should be placed as above, except to be placed at a maximum of 150 mm on centers around the perimeter and a maximum of 150 mm from corner break. Elsewhere, they should be at a maximum of 400 mm on centers except to be placed not more than 150 mm from a longitudinal joint and 300 mm from corner break. In addition to the edge coating of transverse joints, longitudinal joints should be similarly coated with adhesive.

For velocities up to 20 to 30 m/s: fasteners should be spaced as for 10 to 20 m/s. In addition, metal nosing should be installed to secure the liner at all upstream transverse edges.