The thermal insulating glass increases the thermal insulation capability of a PVC, aluminum, or aluminum-wood window. The most basic thermal insulating glass reduces the thermal transfer rate by over 50%, compared with traditional glass. Adding thermal insulating sheets of glass, with colored, reflective and Low-Emision coatings, can greatly increase the thermal performance of PVC, aluminum, or aluminum-wood windows and doors equipped with double-glazed glass, depending on the design requirements.

The thermal insulating glass is made out of two or more sheets of glass, which form airtight chambers filled with air or inert gas,joined by spacer rods sealed in two stages : with butyl and double-component polyurethane
Geam termoizolant

Using thermal insulating glass has many advantages:

Lowering maintenance costs (heating systems, air conditioning)
Nearly complete elimination of the cold areas surrounding windows with thermal insulating glass
In wintertime, the windows allow for a greater intake of sunlight and heat through their glazing system.
In the summertime, they offer a high degree of protection against the transfer of heat from the outside to the inside.

Astra Roger windows are usually equipped with Low-Emision insulating glass. The space between its two sheets of glass is separated by a metallic rod filled with silicagel (granules that absorb moisture)

The width of the glass sheets is usually between 4 and 6 mm. A wider sheet offers increased performance when it comes to thermal and sound insulation.

What you should consider when choosing thermal insulating glass is:
  1. The thermal transfer coefficient U (W/m2K) - the flux of heat which travels over a sqm, in the case of a temperature difference of one degree (under conditions of 0ºC outside,  20ºC inside, and a wind speed of 4.4 m/s)
  2. The light transmittance coefficient T (%) - The percentage of light from the visible spectrum which penetrates the glass. The higher this coefficient is, the better the double-glazed glass is, allowing for a greater quantity of light to get through, which means lowering illumination costs.
  3. The light reflectance coefficient R (%) - The percentage of light from the visible spectrum which is reflected on the surface of the double-glazed glass. The higher this coefficient is, the less visible everything inside of the window becomes from the outside. Glass with a high reflectance coefficient provides your home with privacy and confidentiality, and lowering the need for roller shutters and blinds. Advanced technology allows for the manufacturing of thermal insulating glass which has high transmittance and reflectance, as well as a good solar factor. It is recommended that south-facing PVC, aluminum, or aluminum-wood windows have a lower solar factor, thus reducing costs associated with cooling the room, as well as the discoloration of objects in the room.
  4. The sound insulation coefficient Rw (dB) - defines the window's capacity to abate noise. The higher this coefficient is, the better the glass' sound insulation capacity is, which provides you home with increased comfort and reduces noise pollution.
LowE glass - Low emissivity. It is comprised of a magnetron film that contains several layers of metal oxides, metals, silver or other alloys that are nearly invisible. This layer substantially increases the glass' capacity for thermal insulation, because it reflects a great deal of the heat radiation back into the room, thus reducing the heat loss.

The Planitherm4S Evolution glass - Glass for all 4 seasons. Because it encompasses both the qualities of Low-E glass as well as reflective glass, during wintertime, it has a thermal insulation coefficient of 1.0 w/mpK, but during summertime, unlike Low-E glass, it has a solar factor between that of reflective glass and mass colored glass. In other words, the advantage of  Planitherm4S Evolution glass is that, as opposed to Low-E glass, it offers greater solar protection during the summer months. Yet another advantage, compared with standard reflective glass, is that it has a much higher light transmittance coefficient.
The anti-burglary Duplex glass - It is a type of glass obtained by combining two sheets of glass and a layer of special resin. The most often used is the 6 mm glass, made up of two 3 mm glass sheets, and a 0.38 mm foil/film. In the event this type of glass is shattered, the shards do not come off, lowering the risk of injury. The Duplex glass is recommended for non-residential buildings, which have large glazed surfaces, and helps provide better thermal and sound insulation.

Reflective glass provides privacy for your home, as it doesn't allow viewing from the outside during the daytime. It is obtained through the application of a metallic oxide film on clear or stained glass. This kind of glass is characterized by a high light reflectance coefficient and a low light transmittance coefficient.


Secured glass has a mechanical and thermal stress resistance 3-4 times higher than untreated glass. In the event it is shattered, it decomposes in minuscule shards, nullifying the risk of injury.