Choosing between AuraPlus and FormaPlus Rationel Windows


Rationel offer two main styles of window within their offering of high quality Danish Style Windows.

Key Features FormaPlus

  • Aluminium Clad Wooden frame window
  • 45 degree angled bead and bars – traditional style
  • Classical moulding on the timber interior
  • 83 year life expectancy – independently assessed by Dr Gillian Menzies of the Institute for Building and Urban Design Herriott Watt University, Edinburgh.
  • Available in over 200 RAL colours
  • Dual colour available at no extra cost
  • Textured granite colours available at no extra cost

Best Performance

  1. Triple glazed
    • 0.8 W/m2 K U value
    • 43db Rw sound reduction
  2. Double Glazed
    • 1.28 W m2 K U value
    • 40db Rw Sound reduction

Key Features AuraPlus

  • Aluminium Clad Wooden frame window
  • 90 degree angled bead, bars and interior frame – contemporary style
  • 83 year life expectancy – independently assessed by Dr Gillian Menzies of the Institute for Building and Urban Design Herriott Watt University, Edinburgh.
  • Available in over 200 RAL colours
  • Dual colour available at no extra cost
  • Textured granite colour available at no extra cost

Best Performance

  1. Triple glazed
    • 0.79 W/m2 K U value
    • 42db Rw sound reduction
  2. Double Glazed
    • 1.29 W m2 K U value
    • 40db Rw Sound reduction

Build of AuraPlus and FormaPlus windows

The engineering of the Rationel AuraPlus and FormaPlus windows is superb, with fully engineered timber making up the structure. The wooden finish can have knots within, but these are treated for knot bleed through paintwork. Knots visibility is allowable up to 25mm and not covered by warranty.
The lead time from the point of your order being placed is seasonally dependent – between 6-12 weeks depending on country demand.

Choosing Style and Colour

Windows can transform the appearance of a house. Careful choice of style of window, use of glazing bars on the glass and the choice of colour (including gloss level) of the external powder-coating are all factors that can make a miraculous difference to the finished effect.
See the pictures below demonstrating the effect of good design. This house now has 30% more light, 60% less sound from outside( the owner complained of morning birdsong waking the entire family in spring) 120% improvement in thermal efficiency of the windows, 250% improvement in airtightness and Security exceeding part Q of building regulations.

Replace uPVC with Composite

Rationel AuraPlus windows are a flat frame so the window opener and frame are level with each other thus giving a flush frame composite window. Generally these are seen as suitable for more modern houses but by the careful choice of colour and use of glazing bars these can give a good blend between the traditional and modern.
The AuraPlus Window and FormaPlus window are both the same engineered wooden frame with almost identical performance in terms of U value, airtightness and Secured by Design as standard.
The main differences in the windows are purely decorative and are summarised below.

Exterior Aluminium Cladding

Rationel Exterior Aluminium Cladding

While FormaPlus features the angled glazing bead, commonly found on older windows from both Britain and Denmark, AuraPlus still exhibits a classical throwback. The thin groove on the sash mimics the glazing bead found on an externally-glazed timber window.

Interior Timber Styling

Rationel Interior Timber Styles

AuraPlus continues the external clean lines and 90 degree angles inside. A great solution for those wanting a no-fuss appearance.
On the other hand, the moulded style of the FormaPlus is perfect for those requiring the appearance of an older timber window, without compromising on performance.

Glazing Bars Inside and Outside

Rationel FormaPlus Glazing Bars
Rationel AuraPlus Glazing Bars

The glazing bars on both Rationel products follow the same design cues from their respective outer frames.
Despite appearances, the glass that the glazing bars separate are not individual glass units. There is one single glass unit that fits into the outer frame; a spacer bar is inserted in-between the panes (to give the appearance of separate sections of glass) and the bars are adhered to both sides. This allows the customer to benefit from the appearance they require, without compromising on insulation and airtightness.

Still Unsure on AuraPlus or FormaPlus

Ultimately, do not worry. They are both secure, thermally-efficient and high-quality products. If the styling doesn’t sway you in a particular direction, then we recommend the AuraPlus. Although marketed as a modern window, we have found that, in the correct colour, it can work just as effectively in a traditional project.