EHG G-3® Double Wall Ductwork and Fittings

Duct is of spiral lock seam construction with a mechanically formed seam locking indentation evenly spaced along the spiral seam. All spiral duct 8″ diameter and larger shall incorporate multiple corrugations between spiral seams. Inner and outer duct will be of spiral lockseam construction.

Double wall duct and fittings will consist of a perforated or solid inner liner, 1″ thick x 1.0 lb/ft³ 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. This is to prevent glass fiber tearing into the airstream and maintains the desired acoustical properties.

Standard double wall is 1″ thick insulation. 2″ is also available. The outer pressure shell diameter shall be two times the insulation thickness larger than the inner liner. Fittings shall be manufactured using one or more of the following construction methods:

● Overlapped edges stitch welded along the entire length of the fitting
● Standing seam gore locked and internally sealed
● Button punched and internally sealed
● Elbows 3″ through 12″ diameter will be die stamped and continuously stitch welded

Double Wall Catalog
EHG G-3 Overview
Tolerances, e-dimensions, and Gauges
EHG G-3 Specification
G-3 Assembly Instructions

New Insulation Option: EcoGuard™

EcoGuard™ duct liner is engineered from strong and safe polyester. The hypoallergenic polyester material is webbed into a thermal blanket which is then bonded with a FSK facing to resist damage during system installation and operation. In addition, the facing furthers the liner’s durability, thus protecting the airstream. EcoGuard is engineered to provide exceptional R-values with remarkable noise reduction values.

● High Noise Reduction Coefficient (NRC) value: Provides excellent sound absorption.
● Smooth and extremely durable facing: Reduces damage during fabrication and transportation.
● Made of soft user-friendly and hypoallergenic polyester: Eliminates irritation from handling.
● Engineered for water-based adhesives: Eliminates the need for toxic or expensive adhesives.
● Labor saving alternative to elastomeric duct liner: Saves you time and money.
● Recycled make-up 25%: Increasing sustainability value of the project.
● Mildew and mold resistant: Does not promote nor support the growth of mold or mildew.
● Lightweight design with excellent rebound: Reduces the overall weight of the duct system.

Download the EcoGuard Product Brochure and Safety Data Sheet.

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Contact Info

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Telephone: (877) 482-2344

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