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What is the weakest part of a window?

What part is most exposed to wind, rain and the deterioration over time?

Maybe you have guessed it already…


It is the frame, or more accurately, the frame rebate – the “wet zone” as it is often called, this is where moisture and rain water collects at the bottom of the frame, and can penetrate deep into the frame’s timber construction.

Over time water ingress will cause the timber to deteriorate, and requiring regular maintenance, and possibly replacement of the frame or the entire window.


IDEALCOMBI FRAME – The Original Idealcombi Timber/Alu window

Back in 1988 Idealcombi developed a window that looked like a traditional timber flush casement window, both internally and externally. It had external aluminium cladding, replacing the timber frame in the “wet zone”. This design minimised the need of maintenance and drastically improved the lifespan of the window.

This design made us the first window manufacturer in Denmark to offer a traditional looking alu clad window, with built in weather protection and minimal maintenance requirement.

By replacing the frame rebate – or the “wet zone” – with aluminium we solved the big problem with the perishability of the timber. We are happy to see that the first windows supplied in the 80’s are still working well for our customers.

The Thermal Bridge

In the 1980’s a window’s energy performance was mainly attributed to the performance of the glazing unit.

The demands on a windows’ energy performance changed and we continued our development to introduce a new variation of our timber/alu window. Same visual design but with a thermal break for improved energy performance. The thermal break was an extruded uPVC profile and meant we could maintain the goal of imperishable materials in the “wet zone”.

With the extruded uPVC profiles as a thermal break in the windows, it was necessary to introduce drainage holes and ironmongery grooves. The drainage holes and grooves were great hiding places for bugs and dirt, and would over time get clogged up and cause standing water in the “wet zone”. The standing water then would find it’s way to the internal timber frame and cause deterioration.

Further innovation
The R&D team at Idealcombi kept innovating and came up with a new design that would solve the problems of the drainage holes and ironmongery grooves.

The result of our research and development work is what we call idealcore™ – a thermal break with twice the thermal efficiency of timber, four times the thermal efficiency of traditional composite materials and a lifetime expected to be 70 years or more.

At Idealcombi we believe we have developed the best window design in Europe, based on the following values:

  • Good total economy for the customer
  • Comfort at its best
  • Quality and finish
  • Energy efficiency
  • Aesthetics and design
  • Easy installation
  • Developed to last 70 years or more
  • Environmentally friendly

The latest generation of innovative window design from our development team utilises the benefits of idealcore™ to set the new bar for long lasting, low maintenance, high efficiency windows, with outstanding aesthetics. They are made in Denmark after all!


In other words, we have turned the weakest part of the window into the strongest part! …in every Idealcombi window with idealcore.