Ansicht einer Metalltür im Gebäude
Keeps metal doors in perfect shape

insulbar® shear-free – the dimensionally stable solution for thermally separated external doors

insulbar shearfree patent pending

Usually it’s the weather’s fault when a metal door sticks. If the sun shines, its outer side expands. If it’s cold outside, however, the door bulges inwards. Ensinger now has a new solution to this well-known problem encountered with thermally separated metal doors, the bi-temperature effect (also known as the bi-metal effect): The shear-free insulating profile. It minimises this linear expansion and keeps the door in perfect shape even in the event of extreme differences between the external and internal temperature.

Deformed doors are a thing of the past

The new shear-free insulating bar (patent pending) consists of two intermeshing parts. With temperature-related, differing linear expansion of the inner and outer shells, the two parts shift against one another. This generates a moveable, corrective insulating zone which minimises the bi-temperature effect and evens out the differences in thermal expansion between the aluminium shells.

Illustration of assembly with shear-weak profile Aluminium assembly with normal insulating profile: the large temperature difference causes the door to become deformed.
Illustration of assembly with shear-free insulbar insulating bar Aluminium assembly with shear-free insulbar insulating profile: the flexible insulation zone evens out the differing linear expansion between the inner and outer shells effectively.

All the benefits at a glance

  • Shear-free, consequently a more significance minimisation of the bi-temperature effect compared to shear-weak and shear-resistant profiles
  • Minimal shear rigidity c and low shear strength T
  • Optimised geometry for high transverse tensile strength Q
  • Can be rolled up and laminated like a conventional insulating profile


You can already find the shear-free profile in a variety of sizes between 20 and 42 mm in our standard range. You can also find further information in our brochure insulbar shear-free and in our recommendations processing shear-free profiles.