Nashua 367-17_3X100FT Foil Sealant Tape 3in X 100ft 17 Mil

Product Description

The NASHUA 367-17_3X100FT is a heavy-duty aluminum foil sealant tape engineered for permanent air-tight and water-tight sealing on HVAC duct systems. The tape measures 3 inches wide by 100 feet long and carries a 17 mil total thickness, making it robust enough for demanding sheet metal applications. Construction consists of a conformable aluminum foil backing, an aggressive butyl mastic adhesive, and a blue LDPE film liner that strips cleanly before application. The low-VOC adhesive bonds quickly to sheet metal surfaces and resists moisture and solvents after cure. HVAC technicians and sheet metal mechanics are the primary installers for this product.

This tape is used on residential and commercial sheet metal ductwork where a code-compliant, long-term air seal is required. Typical applications include sealing longitudinal and transverse duct joints, patching sheet metal duct damage, and sealing connections on round, square, or irregularly shaped fittings. The butyl mastic adhesive stays workable for several minutes after initial contact, allowing repositioning in tight mechanical spaces before the permanent bond sets. It is listed under UL 723 and UL 181B-FX, and meets applicable LEED contribution criteria for both energy performance and low-emitting materials.

Key Features

• Aggressive butyl mastic adhesive forms a permanent, water-tight and air-tight seal on sheet metal duct
• 17 mil thickness with conformable aluminum foil backing handles irregular and round duct geometry
• Repositionable for several minutes after application for accurate placement in confined spaces
• Low-VOC content — can contribute toward LEED EQ Credit 4.1 (Low Emitting Materials)
• Resistant to moisture and solvents after cure
• Meets UL 181B-FX requirements for use on Class 1 flex and sheet metal duct systems

Compatibility

Rated for use on sheet metal duct systems and listed to UL 181B-FX for flexible air duct and air connector applications. Suitable for permanent air-tight sealing and repair on round, square, and odd-shaped sheet metal ductwork.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified sheet metal mechanic in accordance with local mechanical codes and SMACNA guidelines. Power down and de-energize the air handling system before beginning duct sealing work. Peel the blue LDPE film liner completely before applying the tape, and press firmly along the full length of the tape to ensure full adhesive contact. Do not apply over surfaces contaminated with oil, dust, or loose oxidation — clean and dry the substrate before installation.