Lacuna bifold doors

Triple glazed timber bi-fold/ foldaside door that meets Part Q security requirements. Suitable for newbuild and retrofit projects.

  • Outward and inward opening
  • High performance triple glazing
  • Heat-treated beech (or oak or mahogany timber)
  • No need to repaint the beech for 20-30 years in normal conditions due to the heat treatment
  • Made in Denmark by Lacuna
  • Meets Part Q security requirements


  • Air permeability EN 12207 – Class 4 at +/-600 Pa
  • Watertightness EN 12208 – Class E1200
  • Security tested to EN1627-30 / PAS24


  • Inward or outward opening
  • Top hung
  • Top rail needs mechanical fixing into structure to stop deflection.
  • Stainless steel hardware
  • Heat treated beech timber as standard (oak and mahogany also available)
  • RAL finish only on heat treated beech, can have woodstain on oak
  • 36mm threshold height
  • No threshold extension option, detail needs to be designed
  • Flat pack delivery, so frame must be built on site and doors hung.
  • Part Q glass –  8mm

Glazing & U values

Whole door U value as low as UD 0.9 W/m2K

Typical maximum sizes

  • Max sizes 6000mm x 2700mm*

Please note: For Part Q and Secured By Design items,  there may be size restrictions. Please get in touch to discuss.

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