Development of a Window for Passive-Housing Featuring an Integrated Sun Shield

Development of a laminated wooden/aluminum window for a passive-housing featuring an integrated sun shield in the shape of blinds or of folding net curtain.

Content Description




According to the values measured, three different types of laminated wooden/aluminium windows with integrated sun shield can be distinguished:



ed[it]ion4 passiv
U-value PHI Feist 0,98 0,92 0,88
U-value measuring ift 0,95 0,89 0,85
g-value 0,55 0,48 0,48
z-factor Jalousie 0,10 bis 0,18 0,09 bis 0,17 0,09 bis 0,17
z-factor Faltstore 0,07 0,07 0,07
Sound absorption 43 dB 43 dB 43 dB

According to the Passiv Haus Institut of Wolfgang Feist a window with an U-value below 0,80 with coating of the inner side of the outlying pane is feasable. Due to the coating a U-value of 0,74 instead of 0,88 respectively 0,78 instead of 0,92 can be reached. Internorm does not, however, offer this product, since the coatings - at present technical standards - lead to streaks during cleansing. The further development of the coating technology is observed carefully by Internorm.

Advantages and disadvantages of the new window


  • More effective in ordering, assembly, and maintenance
  • Shorter period of construction
  • Minimizing thermal bridges due to the ommission of an exterior sun shield
  • Essentially higher lifetime due to integration in window
  • High sound absorption (43 dB)
  • More cost-effective because of the omission of the exterior sun shield, however somewhat higher costs for the laminated window
  • Significantly lower cleaning maintenance of the sun shield
  • Casement and strength of frame are minimized and no wider than they have been
  • Can be applied to facades under monument protection
  • Blinds regulate the incidence of light much more precisely than shutters can do
  • Contrary to exterior blinds, they also work in strong winds


  • Integrated shading may not be as efficient as outside shading but very close to it.
  • Due to physical reasons in combination with certain climatic conditions there can be dew water or mist on the inner side of the outlying pane.

Naming of edition 4

The naming of the new window system is based on the plattform edition by Internorm. The appendix 4 staands for the four technical advantages:

  • Thermal insulation
  • Sound absorption
  • Sun protection
  • Protection against insight

Project Partners

Project manager: DI Thomas Walluschnig
Internorm Fenster International GmbH
  • DI Helmut Schöberl
    Schöberl & Pöll OEG
  • Univ. Ass. DI Dr. Thomas Bednar
    TU-Wien, Institut für Baustofflehre, Bauphysik und Brandschutz, Fachbereich Bauphysik
  • DI Peter Bauer
    Werkraum ZT OEG,


DI Thomas Walluschnig
Internorm Fenster International GmbH
4050 Traun, Ganglgutstraße 131
Tel.: 07229/770/3188
Fax: 07229/770/3151