3M 3340 Aluminum Foil Tape for HVAC Duct Sealing | UL 181A-P / UL 181B-FX

Benefits

• Helps create durable seals on compatible duct systems.

• Supports moisture vapor control in HVAC installations.

• Provides adhesion in both cold and hot environmental conditions.

• Conforms to suitable duct surfaces for convenient installation.

• Helps reduce reliance on mechanical fastening methods in applicable rigid duct board installations.

• Supports long-term performance when properly selected and applied.

Technical Specifications

Property	Typical Value
Product Name	3M™ Foil Tape 3340
Backing Material	High-strength aluminum foil
Adhesive Type	Acrylic pressure-sensitive adhesive
Color	Natural aluminum / silver
Backing Thickness	0.05 mm (2 mil)
Total Tape Thickness	0.09 mm (3.9 mil)
Liner	Paper
180° Peel Adhesion	6.6 N/cm at 23°C
Tensile Strength	50.8 N/cm
Elongation at Break	10%
Long-Term Temperature Resistance	-40°C to 149°C
Standards / Listings	UL 181A-P and UL 181B-FX

Note: Values are typical data from 3M’s technical data sheet and should not be used as guaranteed specification limits. Confirm the current product documentation and applicable listing requirements before specifying the tape.

Applications

• HVAC duct sealing

• Sealing rigid fiberglass duct board

• Sealing flexible, non-metallic air ducts

• Sealing compatible air duct connectors

• Duct closure and insulation system sealing

• Moisture vapor sealing in suitable HVAC assemblies

Compatible Materials

Subject to surface condition and application requirements, 3M 3340 is intended for use with:

• Rigid fiberglass duct board

• Flexible, non-metallic air ducts

• Compatible air duct connectors

• Suitable duct and insulation system surfaces

For other substrates, test adhesion and compatibility before production use.

Industries

• HVAC and building services

• Commercial and residential construction

• Industrial facilities and maintenance

• Transportation and specialty vehicles

• Automotive and general manufacturing

• Maintenance, repair, and operations (MRO)

Why Choose 3M 3340 Aluminum Foil Tape?

3M 3340 combines a durable aluminum foil backing with an acrylic adhesive designed for duct sealing applications. Its UL 181A-P and UL 181B-FX listings make it a candidate for specified rigid duct board and flexible duct applications where the relevant system requirements are met.

For OEMs, contractors, and industrial buyers, selecting the correct tape depends on duct construction, operating conditions, and the applicable installation standard.

Installation Guide

1. Prepare the Surface: Ensure the bonding surface is clean, dry, and free from dust, oil, grease, and loose particles.

2. Check Application Conditions: Follow the product documentation for the permitted surface temperature and application conditions.

3. Cut to Length: Cut the tape to the required length before application.

4. Apply the Tape: Center the tape over the joint or seam and press it onto the surface.

5. Apply Firm Pressure: Smooth the tape firmly to promote intimate contact and minimize wrinkles or trapped air.

6. Inspect the Seal: Check the edges and overlaps to ensure the joint is adequately covered.

Always follow the applicable duct system instructions, local codes, and current 3M technical documentation.

Storage

• Store in the original packaging.

• Keep the tape in a clean, dry environment away from direct sunlight and contamination.

• Avoid excessive heat and humidity during storage.

• Follow the storage conditions and shelf-life guidance stated in the current product documentation.

FAQ

1. What is 3M 3340 Aluminum Foil Tape used for?

It is primarily used for HVAC duct closure and sealing rigid fiberglass duct board, flexible non-metallic air ducts, and compatible air duct connectors.

2. What adhesive does 3M 3340 use?

It uses a pressure-sensitive acrylic adhesive designed for permanent bonding and cold-weather performance.

3. What is the thickness of 3M 3340?

The current technical data sheet lists a typical backing thickness of 0.05 mm and a total tape thickness of approximately 0.09 mm.

4. What is its temperature resistance?

The technical data sheet lists a typical long-term temperature resistance range of -40°C to 149°C. Actual suitability depends on the application and installation conditions.

5. Does 3M 3340 have UL listings?

Yes. It is listed for UL 181A-P and UL 181B-FX applications. Verify that the specific product configuration and intended use meet the relevant requirements.

6. Can 3M 3340 be used outdoors?

Outdoor suitability depends on exposure conditions and the intended assembly. Confirm the product documentation and test the tape under the actual conditions before use.

7. Is 3M 3340 electrically conductive?

It has an aluminum foil backing, but it should not be treated as an electrically conductive adhesive tape without specific supporting data. For electrical continuity or EMI/RFI shielding, select a product specifically designed and documented for that purpose.

8. Can 3M 3340 be converted into die-cut parts?

The paper release liner may support converting operations, subject to tooling, design, and process evaluation. Confirm the required dimensions, tolerances, and production quantities with your converter.

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Downloads

Available upon request:

• 3M 3340 Aluminum Foil Tape Technical Data Sheet (TDS)
• Safety Data Sheet (SDS)
• Product Brochure
• Die-Cutting Capability Guide

Please contact our sales team if you require the latest technical documentation.