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Invisibleunderground installation

High performance ventilation technology for the underground

If rooms should be evenly supplied with fresh air and heated and the air guidance is not possible in the visual area, or rather not wanted, underground air ducts are used.
Underground air ducts generally have two big advantages: They don’t take space in buildings and are opticlaly attractive – because of simply being invisible.

The VENTAFLEX® modular system – well-constructed and versatile.
When leading into the building envelope for example, two technical options are available for selection: the wall collar to be set in concrete or the GRP wall duct.



Project examples

Overall programme


VENTAFLEX® catalog 2020

VENTAFLEX® catalog 2020

All air duct products, technical details, supplies and installation instructions can be found in our general catalog.

Download pdf (8 MB)
Installation instruction VENTAFLEX® air duct round

Installation instruction VENTAFLEX® air duct round

  • Installation of VENTAFLEX® air ducts with VENTASNAP and VENTAFIX
  • Glueing of VENTAFLEX® air ducts
  • Installation of a compensator for the expansion compensation
Download pdf (737 KB)
Installation instruction VENTAFLEX® air duct for underground installation

Installation instruction VENTAFLEX® air duct for underground installation

  •  Recommended measures for installation

  • Application VentaSnap + adhesion

  • Length adjustment of air ducts

  • Creation of a wall duct

  • Installation wall collar

Download pdf (2 MB)


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