The glazing is a construction of two or more glasses, kept apart by a special spacer that is hermetically closed, isolated. The options for combining different types of glass in one common construction are unlimited. The thermal insulation properties, the sound protection and the appearance of the glazing all depend on the correct and most appropriate combination of glazings.
There are several aspects at the base of the glazing of each and every different building, namely:
- Thermal insulation;
- Solar and light control;
- Acoustic insulation;
- Security and safety;
- Architecture, design and decoration.
Important criteria for glazing evaluation:
U: Heat transfer coefficient – generally, this coefficient measures the quantity of energy that goes through given area of the glass per unit of time, evaluated with a difference of 1 Kelvin. The lower the values of this coefficient are, the lower the heat loss through the glazing is.
SF: Solar factor (an indicator for the total amount of solar energy that goes through the glass) – important for air conditioning. The lower solar factor means that there is less solar heat coming through the glass, thus cooling is easier.
TL: Transport light – indicates the percentage of light quantity that goes through the glass in comparison of the entire rayed light. The high percent of light transport is an important condition for the comfort in one’s home.
The glazing of a building can have between 70% and 90% influence on the total energy cost. That is why it is preferable for the glazing to possess the following characteristics:
- Low solar factor;
- High light transmittance;
- Low U-value.