High-tech tuning for your windows.

Keli Window & Door Systems is making use of a sustainable hightech material from the aircraft and wind turbine construction sector for its windows. The heavy frame steel has been replaced with a extremely insulating and stable high-tech PET foam core. The component suitable for passive houses as a supplement to our modular system is unique on the market. evoCore+ achieves significantly better energy efficiency values using the same manufacturing processes. At the same time, you help to ensure the resourcesaving use of materials.

Conventional steel pipe without insulating effect

Highly insulating recycled foam core

– used to stabilise the frame and sash in the classic PVC windo

– used to bolt fittings and install the window

– no insulating function

– high dead weight

– can be bolted, welded

– high stability

– easier assembly due to an element which weighs more than 75 % less than
  conventional steel reinforcement 

– all standard window sizes can be built

– unchanged element sizes compared to conventional reinforcement

– reduced wear on milling and drilling tools in production

A sustainable contribution to climate protection

Thermal insulation

The thermal insulation capacity of the window is improved by approx. 10 %. Keli windows with evoCore+ comply with the passive house standard.

Weight savings

An over 75 % lower element weight compared to conventional steel reinforcement ensures easier installation.
Equally, the energy required for transport along the entire value chain is also reduced.


evoCore+ consists of recycled PET bottles: This means an active contribution to reducing environmental pollution. The material can be reintroduced into the material cycle after use. With evoCore+, the generation of production waste is reduced to almost 0 % since there are virtually no offcuts.

Protection of resources

Valuable contribution to climate protection and the conservation of limited energy resources through the use of up to 100 % recycled PET material.