Glass plays a vital role in protecting interiors from external elements like rain, wind, and extreme temperatures while ensuring transparency and maintaining structural integrity. To achieve these objectives, glass must control several factors, including:
This article focuses on the first two elements—Solar Radiation and Temperature—as moisture and structural load management often involve framing and gasketing systems. Sound control will be addressed in a future article.
Understanding Glass and Solar Energy
Visible light is just a small portion of the electromagnetic spectrum, ranging from 380 to 780 nanometers (nm) or 400 to 790 terahertz (THz). Glass also interacts with other wavelengths of solar energy, such as:
To measure how effectively glass performs, three primary metrics are used:
Optimizing Glass Performance
The goal for most glass applications is to maximize VLT for optimal natural light while minimizing U-value and SHGC to control heat transfer and solar gain. Achieving this balance often involves:
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Future Insights
Glass technology continues to evolve, offering advanced solutions for energy efficiency and environmental control. Stay tuned for upcoming articles that will dive deeper into moisture management, structural loads, and sound control.
The News 04/10/2025
As buildings move toward net zero architecture and glare free daylighting, traditional glass façades reveal limitations: high thermal conductivity (~0.9–1.0 W/m·K), susceptibility to glare, and shattering on impact. In this context, transparent wood (TW) is emerging as a multifunctional bio based material: it offers high light transmission yet strong diffusion (high haze) to prevent glare, lower thermal conductivity than glass, and tough, non shattering failure. Recent reviews in Energy & Buildings (2025) and Cellulose (2023) regard TW as a candidate for next generation windows and skylights in energy efficient buildings. [1]
The News 27/09/2025
Urban flooding is one of the greatest challenges of the modern era, when sudden and unpredictable rainstorms can paralyze entire cities. Few would imagine that over a thousand years ago, people had already discovered a sustainable solution: the Fushougou drainage system in the ancient city of Ganzhou, Jiangxi. Built during the Northern Song dynasty, this project remains effective to this day, protecting the city from floods—even during historic deluges. The story of Fushougou is not only a testament to ancient engineering but also a valuable reference for today’s cities seeking answers to water and flooding problems.
The News 20/09/2025
The construction industry is currently facing immense pressure to reduce carbon emissions, as concrete is not only one of the most widely used materials but also a major source of CO₂ due to its reliance on Portland cement. In response, Shimizu Corporation has conducted extensive research to develop sustainable material solutions aimed at achieving carbon neutrality. One of the most remarkable outcomes is carbon-negative concrete, which partially replaces cement and aggregates with biochar. This biochar is produced from sawdust through a carbonization process and has the unique ability to retain a significant amount of carbon that would otherwise be released into the atmosphere through natural decomposition or combustion. Thanks to this property, carbon-negative concrete not only maintains the necessary mechanical strength for construction but also directly contributes to reducing greenhouse gas emissions. This innovation is considered a promising step that opens new directions for the advancement of green construction in Japan and worldwide.
The News 13/09/2025
In the context of rapid urban development, the risk of fire in high-rise buildings, shopping malls, hospitals, and smart homes remains a serious threat. Traditional fire protection solutions are predominantly passive, focusing only on preventing flames from spreading and lacking sufficient early-warning capabilities. This limitation often results in delayed responses to fire incidents, leading to severe losses in both human life and property. Addressing this challenge, smart walls with integrated fire sensors have emerged as a breakthrough innovation, offering a proactive approach to building safety. Unlike conventional fire-resistant walls, these advanced walls not only provide thermal insulation and fire resistance but also integrate temperature, smoke, and pressure sensors combined with IoT technologies to continuously monitor environmental conditions. At the first signs of fire, the system can instantly detect anomalies, send alerts to a central control unit or mobile devices, and activate additional safety mechanisms such as water mist suppression or smoke extraction fans. By transforming passive barriers into “intelligent fire guardians,” this technology enhances building protection, increases the chances of timely evacuation, and minimizes potential damages. With its ability to turn ordinary walls into active safety components, smart fire-sensing walls represent a proactive solution that contributes significantly to the development of modern, sustainable, and resilient buildings.
The News 27/08/2025
In mass concrete construction, the heat of hydration has always been a “hidden variable” that troubles many engineers and contractors. When cement reacts with water, an enormous amount of heat is generated and trapped inside the massive concrete body. Without proper control, excessive temperatures and the temperature gradient between the core and the surface can cause dangerous thermal cracks, threatening both the durability and safety of the structure. This challenge is not just theoretical—it has been marked in history with a classic lesson: the Hoover Dam (USA), one of the greatest concrete megastructures of the 20th century. Containing millions of cubic meters of concrete, the dam would have taken hundreds of years to cool naturally. Engineers had to devise unprecedented solutions: segmenting the mass, actively cooling it through a network of circulating cold-water pipes, and applying a combination of innovative measures to bring the concrete temperature down to safe levels.
The News 22/08/2025
Have you ever wondered why modern buildings with large glass facades remain cool in the summer yet warm in the winter? The secret lies in Low-E (Low-Emissivity) glass technology. In contemporary construction, glass is no longer just a material for natural lighting but also an essential solution for enhancing a building’s energy efficiency. Low-E glass is coated with an ultra-thin, nearly invisible layer of metal oxide that works “intelligently” to control heat radiation. It allows natural daylight to enter while blocking most infrared and ultraviolet rays that cause heat buildup and potential health risks. Thanks to these properties, this advanced glass not only creates a more comfortable living environment but also significantly reduces heating and cooling costs, while contributing to sustainability and environmental friendliness in modern architecture.
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