Double Wall Insulated Ductwork

Our double wall duct and fittings also control radiated noise better than similar sizes and shapes of externally insulated sheet metal duct.

Double wall insulated ductwork.

It is shipped from the factory with the insulation pre installed reducing job site labor costs. All double wall ductwork and fittings shall be constructed with an outer galvanized wall and a perforated inner galvanized liner. Duct liner shall be of the specified materials thickness and density of the contractors request. Double wall duct has a complete line of compatible fittings.

Insulation it is comparatively easy to insulate a double wall spiral duct compared to a rectangle wall duct. In double wall rectangular duct a metal inner liner insures that high airflow velocities cannot separate insulation by pulling away from the duct s outer wall and creating erosion or airflow problems. Dual wall insulated spiral pipe consists of two concentric spiral pipes with insulation filling the space between the pipes. Thermaduct s inspiral r and floval duct systems are preinsulated spiral and flat oval double wall ductwork alternatives that offer significant weight savings and near zero air leakage.

Ductwork will be spiral seam construction made from g 90 or better galvanized steel conforming to astm a653 a653m and a924 a924m standards lock forming quality lfq. Fittings can be fabricated with standing seam elbow lock or welded seam construction. This double wall insulated ductwork is constructed of a solid metal outer pressure shell and a metal inner liner with a layer of insulation sandwiched between. Cost dual wall spiral duct is relatively affordable compared to the rectangular wall duct.

The acoustical thermal insulation can be used with air velocities up to 10 000 fpm and temperatures up to 250 f. It is insulated from the outer parts compared to the rectangle wall duct which has to be insulated from the inner sections. Double wall duct and fittings will consist of a perforated or solid inner liner 1 thick x 1 0 lb ft layer of glass fiber insulation and a solid outer pressure shell. Dual wall also called double wall insulated spiral pipe.

Double wall duct and fittings can reduce radiated noise by 25 db or more compared with fiberglass duct board and by 30 db or more com pared with insulated flexible duct. When a perforated inner liner is specified a retaining fabric must be wrapped between the perforated inner and the glass fiber insulation. Sheet metal connectors inc. The insulation in our double wall spiral and fittings has both acoustical and thermal benefits.