Last update: 06.09.2019
Thermal insulation
3.

Economy

Technological advances during the last 30 years have produced systems and equipment that can coat glass with razor-thin, neutral high-tech coatings.

Technological advances during the last 30 years have produced systems and equipment that can coat glass with razor-thin, neutral high-tech coatings. This made “ε” emissivity values of thermal insulating glass possible to as low as 0.02 and even lower, whereas for uncoated float glass, ε is 0.89.


However, from an economic perspective, this development and its application in new buildings is just the first step. The next step should be to integrate this new glass technology into the millions of square metres of glazed areas of new and existing windows and façades. This process is almost an automatic one for new buildings today. But existing buildings represent a much greater challenge, and a lot of work must be done in terms of education, explanation and persuasion so that ecological, economic and climate goals can be achieved.


In times of steadily increasing heating energy costs this economic benefit represents a persuasive argument. Just making a simple change, such as glazing involves a fairly short amortisation period and also offers the occupants remarkable improvements in convenience and comfort. See Thermal Insulation Comfort Chapter

The following formula offers one possibility for estimating the energy savings potential provided when replacing outdated glass with modern thermal insulated glazing:

Energy savings


E Savings

Ua U value of your existing glazing

Un U value of your future glazing

F (Glazing area in m²)

G Heating degree day number pursuant to VDI 4710

1.19 Conversion of kilogrammes to litres: 1 litre = 1.19 kg fuel oil

H Heat value of fuel: light fuel oil at approx. 11,800

W Heating system efficiency: oil heater at a 0.85 I Litre

HP Heating season