Wood has great potential applications and is considered an appropriate building material, since it is abundant in nature, its processing is easy and its mechanical properties are satisfactory.

Subject to the selection of the appropriate material and the correct configuration of the cross-section, it has significant advantages, such as the proven stability of the construction and the wide variety of colours. On the other hand, its surface can be painted and repainted, while regular cleaning does not alter its properties or form. The material itself is environmentally friendly, as it belongs to renewable resources, and has very good thermal insulation properties.


Through the frames, the lighting, the ventilation, the audiovisual communication of the building and the passage from one space to another are regulated. Each frame shall meet the requirements of watertightness, windproofness, sound insulation, thermal insulation, wind pressure resistance, solar radiation control, ease of machining, safety, maintenance and durability.

The external frame, regardless of the construction material, is probably the weakest part of the building envelope. For this reason, we must first approach those characteristics to which we must pay special attention and which are generally applicable to all frame constructions.

Poorly sealed windows and doors often result in water ingress or the creation of air currents inside. Moisture usually occurs at the assembly points of the frames at the opening or at the bottom of the glazing. On the other hand, the airtightness problem is mainly found in the frame and sash assembly notches. It is known that most of the heat exchange in a building takes place through the glazing, while to a lesser extent the frame and sash are involved. Wood or uPVC frames have better thermal insulation properties than metal frames. Most issues are observed in buildings constructed before the implementation of the law on mandatory thermal insulation of the building envelope or in those with a high percentage of windows in relation to the rest of the surface. Replacing single glazing with double glazing significantly improves the situation, especially if the gap between the crystals is filled with low thermal conductivity gases. The climatic conditions of Greece require the implementation of a sun protection system, which should be regulated. Another disadvantage of single glazing is that it provides reduced sound insulation. On the other hand, when the distance between the crystals is small (<12mm), the sound insulation behaviour of the frame is worse than that of frames with a single pane of the same weight. For this reason the distance should be as long as possible (>24mm). The situation improves when the crystals have different thicknesses and the gap is filled with heavy gases.


Wood is considered the most suitable material for frames. In recent years, however, its use has been significantly reduced due to the high frequency of damage and architectural forms that have prevailed. The consequence of the former was high repair costs, while the new materials on the market required practically little maintenance. On the other hand, the new architectural forms impose large openings with narrow frame and sash sections. Frames are often placed against the face of the building, with the result that wood as a material cannot support this choice. Most often, the damage is due to the owners’ ignorance of the characteristics of the material, due to which certain basic construction details were ignored in favour of purely morphological elements. When the type and quality of wood does not meet the requirements of the construction, the cross-section is deformed or cracked. However, we must point out that the quality, and not the type of wood, is responsible for the damage.


The selection of timber is based on suitability criteria for the specific use. These criteria are strength, shrinkage properties, processability, drying behaviour, resistance to fungi and insects, resistance to weather conditions, physical condition, colourability and the typical properties of each type of wood depending on its grain. Based on the above, Teak, Afzelia, Wenge, Afroromorsia, Agba, Redwood, Sipo, Dark Red Meranti, Pitch Pine, Iroko, Oregon Pine, Sapeli, Niagon, Carolina Pine, Swedish (Walnut), Pine and Swedish (Somfos) are considered to be the most suitable woods for the construction of frames. Most tropical woods are considered suitable for frames because they combine low resin content with high resistance to weather conditions, while they are not affected by insects and fungi. The main disadvantage is the 20% to 50% higher processing costs. Depending on the type of wood, specific problems occur, such as difficulties in impregnation with protective substances (Oregon Pine) or staining (Afzelia and Iroko), discoloration and corrosion in case of contact with metals (Afroromorsia, Iroko and Sapeli), etc.

All woods with limited weather resistance or susceptibility to fungi are considered unsuitable. In any case, wood whose suitability has not been proven may not be used. According to the German regulations (DIN 68360), the wood must have annual rings with a width of <3mm and straight grain. The following defects are still allowed:

  • Healthy, strong and closed rosettes with a diameter of up to 10mm in visible parts of the frame.
  • Healthy, strong and closed rosettes with a diameter of up to 1/3 of the width of the wood surface in the non-visible parts of the frame. The diameter of the rose should in no case exceed 20mm. On sashes, the size allowed can be up to 50mm.
  • Bumps with maximum dimensions of 5mm width and 50mm length.

In case of cyanosis (spots), the phenomenon should be limited to less than 10% of the surface. If the rose is removed, the direction of the fibres of the insert must be the same as that of the wood. Of the above defects, up to one metre of frame and up to three per metre of frame are allowed. On the other hand, a wood is considered unsuitable for the construction of frames if it shows:

  • Rotational growth greater than 20mm for every 1000mm of length.
  • Cracks in the core or cracks caused by wind and ice.
  • Insect or fungal infestation.
  • Roses on the glazing beams and at connection points.
  • Loose roses in visible parts of the frames.
  • Black or rotten roses or roses with cracks.

Provided that the quality of the raw material is ensured, proper processing prevents serious damage, such as deformation of the frame or sheets, destruction of the glazing, incomplete sealing, etc. These failures are usually due to shrinkage of the cross-sections resulting in the opening of welds and corner joints and the creation of cracks.


We all know the advantages of a wooden window. Being made of a raw natural material, wooden windows provide a sense of comfort and well-being, satisfy every design wish, offer a high heat resistance and do not harm the environment when it comes to their replacement.


The use of wooden windows is the practical application of ecology.

  • Wood is the only material and the only building material that is constantly renewed and combines in an ideal way the economic and ecological aspects. The use of wood is not based on limited raw materials
  • Wood grows thanks to solar energy
  • Among all building materials, wood and wood components require the least amount of energy for disposal, conversion, construction and destruction.
  • As it grows, wood “traps” carbon and accumulates it during its lifetime. this contributes in a very effective way to the reduction of carbon dioxide (CO2), which is largely responsible for global warming.
  • Wood is part of the natural cycle of materials. After their use, wooden frames are an interesting source of energy.
  • Wooden frames are nowadays coated with water-based varnishes and lacquers that do not pollute the environment.

Wooden windows provide a sense of comfort, are part of a healthy dwelling and allow for every design possibility!

  • Wood is the most natural material. The wide variety of types allows to satisfy every wish regarding the layout of the house.
  • The wooden windows offer a sense of well-being and comfort.
  • The wooden surface always has the ambient temperature and is pleasant to the touch.
  • Since wooden windows are not electrostatically charged, they are easy to maintain and are part of a healthy home.
  • In case of fire, wood does not emit toxic gas.
  • Thanks to a new painting that can be done at any time, the wooden frames change colour and get a new look.
  • The various shapes of wooden windows allow for the adaptation of the facades according to individual wishes.
  • Wood is a historically authentic material and therefore its use is mandatory in the windows of historic monuments in most EU countries.

Made with high-tech components, wooden windows are of superior quality.

  • Treated wood and glued wood profiles are extremely stable. They resist heat and deformation.
  • Modern wooden building elements meet every requirement regarding thermal insulation, sound insulation and protection against adverse weather conditions.
  • Due to the good thermal insulation coefficient of the frame material, wooden windows are particularly suitable for houses with low energy consumption.
  • In combination with suitable glazing and window mechanisms, they meet the increased requirements regarding solar protection, protection against burglary or fire resistance.

Wooden windows are long-term economic investments.

  • Wooden windows are structural elements with a long life span.
  • In terms of maintenance, they do not require any more work than other materials.
  • Wooden windows are easy to clean, maintain and preserve.
  • In case of damage, accessories and mechanisms can be easily repaired and reinstalled.
  • They support repeated machining interventions without difficulty.
  • Since the useful average life is longer, wooden windows are more economical than windows made of PVC.