McElroy MetalTrapezoidal Structural — 3" tall

138T / 238T Symmetrical Standing Seam

Trapezoidal 3" tall symmetrical standing seam — high-slope structural panel

Warranty
35-Year Signature 200® Kynar 500 finish
Wind
UL 90 / FM 4471 approvals
Impact
Class A Fire / UL 2218 Class 4
Algae
PVDF Kynar 500® finish

About the 138T / 238T Symmetrical Standing Seam

138T and 238T are McElroy's 3" symmetrical trapezoidal standing seam panels engineered for maximum structural spans and clean, symmetrical seam lines. Ideal for pre-engineered metal buildings, schools, and large commercial roofs.

Key Features

  • 3" tall symmetrical trapezoidal seam
  • Field seamed with electric seamer
  • Long-span structural — reduces purlin count
  • 24 or 22 gauge Galvalume steel
  • Kynar 500® finish palette

Available Colors

22 options
138T / 238T Symmetrical Standing Seam in Regal White — McElroy Metal asphalt shingle
Selected color
Regal White

138T / 238T Symmetrical Standing Seam: The ADC Roofing Deep Dive

McElroy's 138T and 238T symmetrical standing seam panels are engineered for superior structural performance and clean architectural lines, making them an ideal choice for large-span commercial, industrial, and high-slope residential projects in the DFW metroplex. These 3-inch tall trapezoidal panels are designed for structural integrity, capable of spanning greater distances between purlins, which can reduce supporting framework costs. Manufactured from 24 or 22 gauge Galvalume steel, they offer robust protection against the element. The symmetry of the seams allows for reversible panel orientation, simplifying installation and reducing material waste. The panels feature a high-performance Kynar 500® finish, renowned for its exceptional durability and resistance to UV degradation. This is crucial for DFW properties subjected to prolonged exposure to intense sunlight and wide temperature fluctuations. The Kynar finish ensures long-lasting color integrity and protection against chalking and fading, preserving the roof's aesthetic appeal for decades. With a Class A fire rating and UL 2218 Class 4 impact resistance, these panels provide critical protection against fire and the impactful hail experienced during DFW’s severe weather seasons. ADC Roofing’s certified crews are experts in the specialized field-seaming process required for 138T / 238T panels, utilizing electric seamers to create a complete, watertight, and structurally sound connection. This method ensures optimal wind uplift performance, meeting rigorous standards such as UL 90 and FM 4471 approvals. The ability to achieve such high-performance ratings underscores their reliability in DFW environments prone to strong winds and turbulent weather. Choosing the 138T / 238T system provides a commercial-grade, long-span solution that combines structural strength with architectural aesthetics. For DFW property owners and developers, this means investing in a roof that delivers exceptional longevity, performs under extreme conditions, and offers a low-maintenance, visually striking finish backed by a 35-year Signature 200® Kynar 500 finish warranty.

Why 138T / 238T Symmetrical Standing Seam Fits DFW Roofs

The 138T / 238T system’s Class 4 impact resistance is vital for DFW’s hail season, while its Kynar 500 finish ensures color stability under intense heat. Its structural properties make it excellent for large commercial buildings and custom homes requiring high wind resistance, often exceeding typical HOA and insurance requirements due to its robust nature.

How ADC Installs 138T / 238T Symmetrical Standing Seam

ADC Roofing installs 138T / 238T panels using specialized electric seamers to create the 3-inch symmetrical trapezoidal seam. We adhere strictly to specifications for proper panel securing and thermal expansion, ensuring the roof meets all structural and wind uplift ratings for maximum performance and warranty adherence.

138T / 238T Symmetrical Standing Seam — Frequently Asked Questions

Q.What advantages do the 138T / 238T panels offer for large DFW commercial buildings?

Their 3-inch tall trapezoidal seam and structural design allow for longer spans, potentially reducing the required purlin count and overall frame costs, while providing superior wind and hail resistance critical for DFW structures.

Q.How does the Kynar 500 finish on these panels benefit properties in DFW's climate?

Kynar 500 is highly resistant to color fading, chalking, and UV degradation, ensuring the roof maintains its aesthetic appeal and protective qualities for decades despite DFW's intense summer sun and temperature fluctuations.

Q.Are these panels suitable for high-end residential or custom homes in DFW?

Yes, their clean lines, structural integrity, and durability make them an excellent choice for modern or architecturally significant residential properties requiring a high-performance, long-lasting metal roof.

Q.What is involved in the 'field seaming with an electric seamer' process?

This process involves using a specialized machine on-site to mechanically crimp the panel seams, creating an extremely strong, watertight, and continuous connection that enhances the roof's integrity and wind resistance.

Q.Will installing the 138T / 238T system help with attic ventilation for DFW heat control?

Metal roofing naturally reflects more solar radiation than asphalt. When combined with ADC's expert attic ventilation strategies, it significantly contributes to reducing attic heat gain and lowering cooling costs in DFW homes and commercial buildings.

About McElroy Metal

McElroy Metal is a leading manufacturer of standing seam metal panel roofing products. ADC Roofing is a certified McElroy Metal installer serving the entire Dallas–Fort Worth Metroplex, with in-house crews trained on McElroy Metal's installation specifications and warranty requirements.

We stock 138T / 238T Symmetrical Standing Seam samples in our Southlake showroom and can deliver full-size color chips to your home. Every McElroy Metal installation from ADC includes manufacturer-certified underlayment, ridge ventilation, and starter strip — a complete factory-spec system.