Build Sustainably

In today's increasingly eco-conscious society, sustainable construction is a concept that certainly cannot be overlooked. This type of construction is based on low-energy, organic products from completely natural materials with a minimal impact on the environment.
Rising environmental awareness among the population and growing demand for organic, environmentally acceptable materials can be witnessed in Slovenia just as in Austria, Germany, Switzerland and everywhere else in the developed world.

Being a vital architectural element of the external envelope of any building, windows and doors are one of the key elements in terms of energy efficiency. Today, the external joinery market remains dominated by products with slightly inferior thermal insulating characteristics. This occurs despite all calculations and measurements showing how, by installing energy efficient windows and doors, up to 50% of the financial resources intended for heating can be saved only in terms of energy.

There are many factors affecting the thermal efficiency of joinery.

The most significant among them are the structure of windows, the material which their frames are composed of, the way the framework and casement are sealed, the type of glazing and the way the framework and the glass are joined together. The efforts made, in terms of thermal conductivity, used to be focused on glazing, through which depending on its thermal characteristics and share of the glass surface on the product, the major part of heat loss occured.

In recent years, special attention regarding thermal characteristics has been paid to glazing, which results in this element's superior thermal values today. Available on the market for some time now is three-layer glazing with a thin, low-emission coating and filled with noble gases such as Argon or Krypton, achieving excellent thermal characteristics of up to 0.4 W/m2K. Along with the development of plastic spacers (Termix, TGI), the thermal characteristics of glass have improved up to the point where now it is joinery, i.e. the area of frame and casement, that has become by far the weakest part of the external building envelope in terms of heat loss and, consequently, the main culprit for energy-wasteful buildings.

Only representing 10 to 35 per cent of the overall window surface, the frame has much poorer thermal characteristics than glass. As a result, up to 50% of the total heat loss may occur through it. With their higher percentage of framework surface compared to the glass portion, smaller-sized windows, as a rule, provide inferior Uw thermal values. The same applies for twin or multiple casement windows.

The LEOPOLD FENSTER SOLUTION range of window profiles made of laminated wood with built-in rigid polyurethane foam as insulation follows the trend of more economical, low energy construction.