Efficient solar control: when glass façades become thermal challenges

Large expanses of glass form an integral part of modern architecture. However, during summer months they often lead to overheating and glare. Innovative solutions developed by the glass industry provide an answer to these challenges.

Extensive glazing allows plenty of daylight to enter buildings and creates a link between indoors and out that typifies modern architecture. During the summer months, however, it is precisely this property that can become a challenge. Glass not only permits light but also part of the solar energy to enter the building. With clear float glass the total solar transmission rate is comparatively high. This is where state-of-the-art solar control glazing comes in.

Modern solar control coatings are designed to allow the entrance of daylight while reducing solar gains. They can reduce the g-value without darkening interiors significantly. For both new buildings and refurbishment this is a key approach to better link transparency with comfort.

Electrochromic glass takes this approach to the next level. It changes its tint upon command, by switching, remote control or automatically via sensors. When exposed to strong solar radiation it turns darker thereby reducing solar heat gain without completely blocking the view outside.

Photochromic films are a power-free alternative to also upgrade existing buildings. They darken automatically in response to light intensity – similar to photochromic lenses. How this technology works and what potential it holds for the energy-efficient refurbishment of existing buildings is explained by Julia van der Burgt at ClimAd Technology in the glasstec-Interview.

• 1) Baunetz Wissen: Gesamtenergiedurchlassgrad (g-Wert) (Retrieved on 16 April 2026)