Thermally insulating glass

1. technical data

Dimension max. 3210 x 6000 mm


Glass type (CLIMAPLUS ULTRA N) Light transmission τv to DIN EN 410 in % Total Energy transmittance
(g-value) to DIN EN 410
Ug- Value to DIN EN 673 in W/m².K*
4 / 10 K / 4 mm 80 63 1,0
4 / 12 K / 4 mm 80 63 1,0
4 / 16 Ar / 4 mm 80 63 1,1
4 / 12 Ar / 4 mm 80 63 1,3
4 / 16 A / 4 mm 80 63 1,4
4 / 12 A / 4 mm 80 63 1,6

* Ug-Values only valid for vertical glazing

Ar = Argon filled cavity
A = Air filled cavity
K = Krypton filled cavity ( ≥ 92%)



U-Values given relate exclusively to vertical glazing. U-Values for sloped or horizontal glazing are worse. In European Standard EN 673 Point 5.3.1 and 5.3.2, values for the calculation of horizontal glazing are given.
As an example, a Ug-Value of 1.1 W/m²K in vertical glazing increases to 1.7 W/m²K when horizontally installed.

The Ug-value tables to DIN EN 673 show the performance of insulated units at a glance. The tables have been created by ift Rosenheim and indicate the given values in accordance with the European standard.


2. Edge Seal

2.1 Standard composition

2-Sheet insulated glass with, aluminium spacer bar – bent corners, with dual seal system, primary seal of Polyisobutylen and secondary seal of Polysulphide.

2.2 UV-resistant edge seal / Silicon Structural Glazing

It is possible to achieve a gas-filled UV-resistant cavity using silicone as the secondary edge seal and CHROMATECH PLUS spacer bars.
The requirements of EN 1279-2 are fulfilled by such insulated units. The requirements given in this Eurocode have been substantiated in test report TC-RAP-06-18364 .

Warm-Edge – Thermally improved spacer in accordance with EN 10077-1

In addition to conventional aluminium spacer bars, the CLIMATOP range of insulated units are also available with thermally improved materials. This „Warm-Edge“ system reduces the warm bridge at the edge of the unit and improves the UW-Value of the window. Simultaneously the possibility of condensation at the edge of the unit is minimized or even eliminated.

The window-integral warm bridge is characterized by the linear thermal transmittance coefficient ψfg or „ψ-Value“ and is taken into account when calculating the UW-Value of the window.

For fixed glazing, e.g. in a transom/mullion framing system – different values are achieved. These are given as ψmg (Mullion) and ψtg (Transom).


The preferred method for determining the linear thermal transmittance coefficient (ψ) is a calculation to EN 10077-2. Such calculations are to be carried out by the framing manufacturer, whereby the value to use for CHROMATECH PLUS is 0,004 (to EN 10077-1, E3). This is approximately 40 % better than the minimum required value of 0,007.

Frame material Linear thermal transmittance coefficient Ψ W/m.K
Wood/PVC 0,048 0,08
Metal with thermal break 0,065 0,11

CHROMATECH PLUS can reduce the Uw-Value of windows – dependent on the frame material – by approx. 0,1 W/m².K. The tendency toward condensation in the insulated glass edge seal is visibly reduced.

For window frames it is possible to use simplified standard values in accordance with appendix E2 and E8 of the above mentioned Code.

CHROMATECH PLUS black is available for cavity width of 10, 12, 14, 16, 18, 20 mm.

Standard composition CLIMAPLUS
Comparison CHROMATECH PLUS to conventional Aluminium spacer
Optically appealing surface appearance of a typical Warm Edge Design in CHROMATECH PLUS