Ductwork stiffeners

Gebhardt Ductwork Stiffeners are fitted to the outside of ductwork to reinforce the ductwork and to reduce vibrations.

The stiffeners enable you to reinforce ductwork in a simple and cost-effective way. Pre-drilled holes ensure a convenient fixing.

The stiffeners are also suitable to reinforce already fitted ductwork, as the stiffeners can be fitted to the completed ducts.

  • conforms to DW 144 Specification Figure 26
  • available with S3 rating (Stiffener S3 40x30mm)
    and S4 rating (Stiffener S4 50x40mm)
  • no need for retrospective painting of black angle iron
  • pre-drilled holes down each length
  • Stiffener S3

    Stiffener S3

    • Art. No. 313 300 010
    • Galvanized steel Z275
    • Pre-drilled holes for fixing
    • 40mm x 30mm x 1.75mm
    • Length 5m, PU 250m
    Gebhardt-Stahl GmbH
  • Stiffener S4

    Stiffener S4

    • Art. No. 313 310 010
    • Galvanized steel Z275
    • Pre-drilled holes for fixing
    • 50mm x 40mm x 2.00mm
    • Length 5m, PU 250m
    Gebhardt-Stahl GmbH




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Gebhardt-Stahl GmbH

We have been manufacturing cold-rolled metal sections in Werl for more than 30 years. We’re an innovative medium-sized enterprise and focus on the production of steel reinforcement sections for PVCu windows, HVAC components, steel vineyard stakes and bespoke profiles.


Gebhardt-Stahl GmbH

Runtestraße 33
59457 Werl

+49 (0) 29 22 / 97 33 - 0

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