Innovations in windows technologies in recent years allow creating more energy-efficient homes. Solar gain adjusting, condensation reduction, air leakage prevention, and creating a healthier indoor environment have become possible with a variety of glass glazing and coating and improved frame options. Energy-efficient windows are making possible carbon emission reduction comfortably and sustainably. Ecological materials with smart design solutions create an attractive and safe home.

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Windows are an essential component in sustainable building design. Windows connect the house to the outside world drawing in air and holding temperature. Choosing an eco-friendly windows option for the house is beneficial not only for the planet but for the homeowner’s pocket. Inefficient windows can raise energy bills by 30% letting the heat escape from the building. The passive design concept suggests that the windows should be the first consideration for energy performance optimization providing efficient heating, cooling, and lighting indoors. Window’s size, materials, shape, direction, frames, curtains are the important factors not only making the housing more attractive and comfortable but also energy-saving and advantageous for the planet. 


The advantages of the eco-friendly windows:

  • saving on air-conditioning and heating costs,

  • improving insulation,

  • reduction of UV rays, which fade furniture and other objects indoors,

  • frost and condensation reduction,

  • durability and safety,

  • protection from outdoor sounds and noises,

  • low maintenance,

  • better sleeping and health conditions,

  • environmental care.


Window energy ratings

Selecting energy-efficient windows has become easier with the system designed by the British Fenestration Rating Council. Windows are classified using labels from A to G, with A-C being the most efficient and G being with the lowest performance. Unfortunately, the classification does not include windows’ size and direction but indicates overall efficiency. 

The factors of the windows included in the calculation:

  • U-Value is the thermal efficiency indicator testing the heat loss from the window,

  • G-Value or solar gain measures the amount of heat used from the sunlight,

  • L-Value or air leakage measures the draughts or amount of the air leaking in and out of the window. 


Eco-friendly windows materials

A wide selection of materials is manufactured for the windows today. Considering their environmental impact, thermal and acoustic performance, maintenance peculiarities are important for sustainable home creation.  

Timber is an exceptional insulator functioning well in extreme weather conditions. Wood is a recyclable and biodegradable material, which helps reduce our dependence on fossil fuels. It is a great hypoallergenic and non-toxic material creating a natural and healthy atmosphere in a home.

Glass is now available in many glazings and with different characteristics impacting the energy-efficiency of a building. Glass is sustainable, fully recyclable, and reused repeatedly for different new products throughout the lifetime.

Aluminum is a recyclable material used mainly for fixtures due to its strength and durability. 

Vinyl is an energy-efficient material requiring little maintenance. The material is long-lasting and highly recyclable to manufacture new vinyl products. 


Tips on energy-efficient windows design

  1. South-facing building windows harness a lot of passive solar energy keeping the temperature warm indoors. On the opposite, the east- and west-facing windows tend to cause the most energy waste. 

  2. Pay a lot of attention to the window frame selection. Aluminum, wood, and vinyl are the most common recyclable and energy-efficient options, while fiberglass is not recyclable. 

  3. Not all glass is the same! Double-pane and triple-pane windows will reduce the heat flow in winter, although they are heavier, which has to be considered for the frame choice.

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