Double Wall Insulated Ductwork

Sheet metal connectors inc.

Double wall insulated ductwork.

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. 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. 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. Duct liner shall be of the specified materials thickness and density of the contractors request.

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. 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. Constructed of a solid shell surrounded by a layer of insulation and covered by a solid outer shell.

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. Fittings can be fabricated with standing seam elbow lock or welded seam construction. It is insulated from the outer parts compared to the rectangle wall duct which has to be insulated from the inner sections. Our double wall duct and fittings also control radiated noise better than similar sizes and shapes of externally insulated sheet metal duct.

It can reduce radiated noise by 25 db or more compared to fiberglass duct board. 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. Cost dual wall spiral duct is relatively affordable compared to the rectangular wall duct.

Zen s 1 inch insulation has a thermal conductance of 0 27 btu hr x sq. Double wall duct has a complete line of compatible fittings. The insulation in our double wall spiral and fittings has both acoustical and thermal benefits. Dual wall also called double wall insulated spiral pipe.