TDF vs Flanged Ducts: Which is the Best HVAC Ducting System in 2025?

Category: HVAC Ducting | Tags: TDF Ducts, Flanged Ducts, Sheet Metal Ducting, HVAC Systems, Duct Manufacturer India

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FACTORY FABRICATED RECTANGULAR TDF DUCTS

Introduction: Choosing the Right Ducting System in 2025

When it comes to commercial and industrial HVAC systems, one of the most critical design decisions is choosing the right duct joint system.

Two common types are TDF (Transverse Duct Flange) and Conventional Flanged Ducts.

In this blog, we’ll break down:

• What TDF and Flanged ducts are

• Their pros and cons

• How they affect air leakage, cost, and installation

• Which one you should use in your next HVAC project

What is TDF Ducting?

TDF (Transverse Duct Flange) is a self-flanging duct system where the duct edge is shaped into a flange during fabrication—no need for external angle frames.

Key Features of TDF Ducts:

• Fabricated using TDF roll-forming machines

• Strong corners with minimal air leakage

• Fast installation, ideal for SMACNA-compliant projects

• Lightweight and cost-effective for transport

Popular in: Commercial HVAC projects, cleanrooms, high-rise buildings, hospitals, malls

What is a Flanged Duct?

Flanged Ducts use external angle irons or cleats riveted or welded to the duct ends to create a flange system.

Key Characteristics:

• Time-consuming manual fabrication

• Prone to alignment errors and leakage

• Typically used in heavy-duty industrial ducting

Popular in: Industrial HVAC systems, retrofits, non-standard installations

Why TDF Ducts Are Better for Modern HVAC Projects

TDF ducting is now the preferred choice of MEP consultants, architects, and HVAC contractors due to:

• Time and cost efficiency

• Cleaner installation

• Compliance with global standards like SMACNA and DW/144

• Compatibility with automated fabrication lines

SAMCOFLEX’s TDF Duct Advantage

At SAMCOFLEX, we manufacture custom TDF ducts in our state-of-the-art facilities in Noida and Hyderabad. Our TDF systems are:

• Fabricated using CNC-controlled TDF roll formers

• Built to international standards (SMACNA, IS, ASTM)

• Available with optional EPDM gasket sealing

• Backed by quality testing and on-time delivery

Use Cases Where TDF Ducts Outperform

• High-rise commercial buildings

• IT parks and office complexes

• Cleanrooms & pharma units

• Projects with tight timelines and modular HVAC systems

Conclusion

TDF ducts are the clear winner in most modern HVAC ducting applications. They offer better speed, reduced leakage, and higher reliability.

Flanged ducts still have their place in heavy-duty setups — but for cleaner, cost-efficient air distribution, TDF is the future of ducting.

Want to know if TDF ducts are right for your project? Talk to a SAMCOFLEX expert today.