LAMILUX Passive house flat roof window: Energysave+

Certified daylight system for the "cold" climatic zone

The LAMILUX CI System Glass Element FEenergysave+ is the world's first skylight suitable for passive houses in Scandinavia and many regions of Austria, Switzerland and Eastern Europe. As a further development to our LAMILUX CI System FEenergysave, it meets the criteria for the cold climate zone and has been awarded the top Passive House classification, phA.

Design details


  • Quadruple-glazed ISO glass with krypton fill fitted as standard
  • Top Passive House efficiency class – phA advanced component
  • Thermal transmittance coefficient USL 0.68 W/(m²K)
  • Minimised risk of condensate thanks to stable fRSI- value of 0.76
  • Low heat loss and high solar heat gains (ψopak ≤ 0.110 W/(mK))
  • Accessory range same as FEenergysave

    Passive House certification in twin pack

    Cold climate zone + cool temperate climate zone

    In addition to the world's first Passive House certification for the cold climate zone, our LAMILUX CI System Glass Element FEenergysave+ has been awarded the top efficiency class for the cool temperate climate zone.