Insulate your house yourself with plastic additional windows

As a result of the energy crisis and the need to reduce gas consumption, we notice that the demand for secondary windows is increasing. It is very easy to make an additional plastic window yourself to provide additional insulation for your home. Lakwijk supplies custom-sawn, crystal-clear plastic sheet material with a hole pattern of your choice.

An additional window is an easy and budget-friendly way to properly insulate single-glazed windows. This is a simple way to save on your energy consumption. It is an extra window that you simply place on an existing window. In addition to insulation, an additional window provides extra protection to the window and has a sound-resistant effect. With clear additional windows you can choose from two types of plastics:

  • Acrylic, for example from the Plexiglas brand
  • Polycarbonate, for example from the Arla brand

Acrylic is the most obvious choice. If protection against vandalism or burglary is also required, polycarbonate is a better choice. Moreover, polycarbonate is self-extinguishing.


The thermal conductivity coefficient indicates how well a material insulates. The lower this value, the better the material insulates, so the higher the insulation value. Acrylic has a thermal conductivity of 0.19 W/(km) and polycarbonate 0.20 W/(km). This is significantly lower than the conductivity of single glass (float glass), which has a value of 0.80 W/(km). Plastic secondary windows are an easy way to save on your energy consumption!

Please contact us for more information.

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