Double Wall Insulated Ductwork

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.

Double wall insulated ductwork.

It is shipped from the factory with the insulation pre installed reducing job site labor costs. Dual wall also called double wall insulated spiral pipe. Insulation it is comparatively easy to insulate a double wall spiral duct compared to a rectangle wall duct. 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.

When a perforated inner liner is specified a retaining fabric must be wrapped between the perforated inner and the glass fiber insulation. 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. Double wall duct has a complete line of compatible fittings. Sheet metal connectors inc.

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. Dual wall insulated spiral pipe consists of two concentric spiral pipes with insulation filling the space between the pipes. 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. 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.

It can reduce radiated noise by 25 db or more compared to fiberglass duct board. Duct liner shall be of the specified materials thickness and density of the contractors request. The insulation in our double wall spiral and fittings has both acoustical and thermal benefits. The acoustical thermal insulation can be used with air velocities up to 10 000 fpm and temperatures up to 250 f.

Fittings can be fabricated with standing seam elbow lock or welded seam construction. Cost dual wall spiral duct is relatively affordable compared to the rectangular wall duct. It is insulated from the outer parts compared to the rectangle wall duct which has to be insulated from the inner sections. Constructed of a solid shell surrounded by a layer of insulation and covered by a solid outer shell.