Thermaduct by Sheet Metal Connectors, Inc.

Exterior Pre-Insulated Weatherproof Ductwork

Sheet Metal Connectors is a licensed manufacturer for Thermaduct,™ pre-insulated ductwork that’s designed for use in exterior weatherproofing and rooftop applications. Thermaduct provides insulation, duct and cladding all in one high-efficiency duct system.

Exterior Ductwork Insulation That’s Different

With Thermaduct, avoid the standard cladding issues, corrosion and leakage that leads to eventual exterior duct failures. Thermaduct can be installed using a gasketed 4-bolt connection with weather-resistant covering at all transverse joints.

Advantages of Thermaduct Insulation

Thermaduct is fabricated following the SMACNA Phenolic Duct Construction Standard. Its vinyl cladding supplies a strong, seamless surface which eliminates water intrusion areas to provide a tough and weatherproof exterior. Up to three corners of its 1,000 micron cladding can be bent thermally, leaving no seams with the final corner solvent-welded for water-tight protection.

Thermaduct exterior duct phenolic exceeds existing ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) and ICC (International Code Council) Energy Codes.

Thermaduct panels are available in the following insulation types:

  • R-8.1 (1x 1 3/16″)
  • R-12 (1 x 1 3/4″)
  • R-16.2 (2 x 1 3/16″)
  • R-20 (1 x 1 3/4″ & 1 x 1 3/16″)
  • R-24 (2 x 1 ¾”)

Benefits of Thermaduct insulation include:

  • Passes the UL181 mold growth test
  • Closed cell insulation
  • Proven low air leakage
  • UV stable, 1,000 micron vinyl cladding
  • Made in the USA
  • Made in our union shop

Compliance Testing

Thermaduct is designed for exterior duct applications to help withstand tough conditions. Thermaduct incorporates the following standards for testing and compliance, making it a true solution for weatherproofing and exterior ductwork:

ASTM D-638, ASTM D790, ASTM D-256, ASTM D-4226, ASTM D-4216, ASTM D-792, ASTM D-2240, ASTM D-696, ASTM D-648, UL-94 Exterior Cladding

Thermaduct Insulation Color Choices

Available in three colors — white (standard), tan, and gray vinyl — Thermaduct is tested for UV stability, durability, low thermal transfer, and heat deflection and buildup. Its 1,000 micron cladding is up to 5 times thicker than exterior duct protection offered by other manufacturers.

All SMC custom sheet metal products, including Thermaduct insulation, are designed and manufactured in our yellow label union shop. View the Contractor Installation Manual, get access to product training courses or explore submittal information.