138T & 238T

While standing seam roofing systems have been used for generations, 138T and 238T panels feature technological advances in roofing that set a new standard for standing seam performance. 138T and 238T systems are classified as symmetrical standing seam systems and offer many advantages including patented recover solutions featuring the industry's best method to recover existing metal or shingle roofs.  138T and 238T panels are mechanically seamed along with the seam caps. Mechanical seamers and hand crimpers are available for rent through Developmental Industries (DI) at mcelroyseamers.com, a website created just for McElroy customers. The rental fees for each type of equipment can be found on this site as well as additional information you may need to be aware of within the terms and conditions. DI is the only approved supplier for this type of equipment.  

 138T and 238T advantages include:

View an installation animation 


  • 138T minimum slope: 2:12
  • 238T minimum slope: 1/2:12
  • 238T subject to prior approval, 1/4:12 may be acceptable
  • 138T must be installed over solid deck
  • 238T can be installed over solid deck or open framing

  • 138T & 238T are mechanically seamed profiles

  • Oil Canning is a natural occurrence in metal panels and is not a cause for panel rejection



Testing Data

138T & 238T

  • Uplift Test - UL580 Class 90, UL 1897 and ASTM E1592 
  • Fire Rating:  UL Class A
  • Impact Resistance:  UL Class 4
    FM Class 1-SH

238T Only

  • Uplift Test: FM 4471
  • Air Infiltration: ASTM E1680
  • Water Infiltration: ASTM E1646
  • Static Water: FM 4471 Appendix G, ASTM E2140
  • Texas Department of Insurance Approval: RC-270
  • Florida State Approval: FBC #16606.1, 16606.2, 16606.3
  • Miami Dade Approval: NOA #15-1216.03
  • ICC-ES Approval: ESL-1082

  • For any available Test Data, Section Properties and Load Tables, please visit our downloads section


Panel Options

  • Panel height & width:
    138T: 1 3/8" x 12" or 16"
    238T: 2 3/8" x 16", 18", 24"
    238T 24" Panel formed on-site only
  • Panel Configurations:
    138T: flat, striated, plank & pencil ribs, plank, minor ribs
    (plank & pencil rib recommended)

    238T: flat (16" & 18" only), striated, plank & pencil ribs, plank, minor ribs
    (plank & pencil rib recommended)
  • Coating:
    - Kynar 500® (PVDF)
  • Substrate:
    - Standard 24 GA Galvalume®
    - Optional 22 GA Galvalume
    - Optional .032 and .040 aluminum
    - Optional 16 oz and 20 oz copper
      (Houston Plant Only)
  • 138T & 238T Manufacturing: factory, jobsite roll-formed, curved on-site

Curving Information

  • 138T panels can be curved (16” width only)
  • 238T panels can be curved (16”, 18” widths only) 
  • 138T, 238T and Multi-Span Clips are curved onsite by McElroy curving technicians
  • Minimum Radius:  
    138T - 8’ radius 
    238T – 24’ radius
    Multi-Span Clips - 35’ radius
  • Maximum length on Multi-Span clips is 30’
  • 138T flat panels will curve naturally on a radius of 150’ or greater
  • 238T flat panels will curve naturally on a radius of 225’ or greater

Curving Photos

Click image to enlarge