The insulating double glazing glass increases the thermal performance of PVC windows, aluminum or alu-wood. The simplest package window heat reduces by over 50% rate of heat transfer by comparison with traditional monolithic glass.
By adding layers of glass with layers of thermal color cover, reflective and LowE you can increase considerably the thermo performances of PVC, aluminum or alu-wood with double glazing glass windows and doors, depending on design requirements.

Insulating DOUBLE GLAZING glass is made of two or more sheets of glass that form the tightly closed room in which there is air or inert gas, connected by rods sealed in two stages: with butyl and double-component polyurethane.


Using the thermo insulating glass can get you numerous advantages:

  • Reduction of maintenance costs (heating systems, air conditioning)
  • Eliminates almost entirely cold areas near the double glazing windows
  • Winter: Thermopanes retain the sunlight and heat through the glass
  • Summer: Thermo insulating glass offers high protection against heat penetration from the outside or inwards

FereAstra Roger is standard equiped with LowE glass. The space between the twp glass sheetsis is maintained through a metallic rod filled with silicagel. The glass sheets's width can vary between 4-6 mm. A greater width of the glass sheet offers high performance.

Indicators to be taken into account when choosing the window:

  1. Thermo Transfer Coefficient U (W/m2K) - the heat flux that crosses a surface of a square meter under the conditions of a single centigrade degree - difference between the inside and outsite (applied to a 0ºC temperature, an interior termperature of 20ºC and a windspeed of 4.4 m/s)
  2. Light transmission Coefficient T (%) - represents the light percentage that is transmitted through the glass. Higher the coefficient, the more performance the glass delivers, allowing more light to pass, thus reducing the expenses.
  3. The Light Reflection Coefficient R (%) - represents the light percentage that is reflected by the double glazing glass. Higher the coefficient, fainter the eye perception beyond the glass. The glass having such a high coefficient assures intimacy and the confidentiality of your home, avoiding the need to bur shutters or window blinds. The advanced technologies have allowed creating a thermo insulating glass that has both solar transmission / reflection and acceptable solar factor. We reccomend that the PVC double glazing windows from the southern oriented buildings should have a low solar factor glass, thus reducing the cooling costs.
  4. The Sound Insulation Coefficient Rw (dB)defines the ability of the double glazing PVC or aluminum windows to attenuate the noises. Higher this coefficient, better the window can insulate. This offers the so much needed tranquility of your home, but also an increase in comfort


The main glass types are

LOW-E Glass (low emissivity) - is in fact a magnetron film that contains several layers of metal oxides, metals, silver or other alloys that are nearly invisible. This layer increases substantially the thermo insulating properties of the glass, because it reflects a great deal of the heat radiation back into the room, thus reducing the heat loss.

Four Season Glass - It includes both LowE and reflexive glass properties: during winter, it's heat insulation coefficient is 1.1 w/mpK. During summer, apart from he LowE glass, it has a solar factor that is somewhere between a reflexive and a colored glass. That is why we must emphasize that the FOUR SEASON GLASS has a better advantage.

ANTI-BURGLAR DUPLEX Glass - Is a type of glass obtained through combining two sheets of glass and a layer of special resin. The most common is the 6 mm glass, made of two 3 mm sheets and a 0.8 mm film. If this glass breaks, the fragments don't shatter and fall, thus reducing other accident risks. This duplex type of glass is recommended for non-residential buildings, where the window surface is large.

REFLEXIVE Glass - assures the intimacy of your home. It doesn't allow viewing from the outside, during daytime. This type of glass is obtained by applying a metal oxide film on a clear glass or mass colored. This type of glass is defined by a high solar recletion factor and a low light transmission factor.

The SAFETY glass has a 3-4 times greater resistance to the mechanical and thermo stress than untreated glass. If broken, it shatters into very small pieces, reducing to zero any risk of injuries.