The real carbon cost of glazing
By Jon Vanstone, chair of Certass.
Sustainability is no longer a side consideration in the glazing industry – it is at the heart of how we must operate.
With carbon reduction targets becoming ever more pressing, the conversation around the environmental impact of our products has never been more relevant.
While glass recycling schemes are an important step in the right direction, sustainability goes beyond recycling alone. To truly address the carbon footprint of glazing products, we need a holistic approach that considers embodied carbon across the full lifecycle of products and materials.
Embodied carbon refers to the greenhouse gas emissions associated with the extraction, production, transportation, installation, maintenance, and disposal of building materials. The challenge for the glazing sector lies not just in making systems more thermally efficient but in ensuring that their production is as sustainable as possible.
Glass manufacturing is energy-intensive, requiring extremely high temperatures to melt raw materials. This process results in significant carbon emissions, contributing to the embodied carbon of glazing products. Some manufacturers are addressing this by incorporating more recycled content, reducing the need for virgin raw materials and cutting energy use.
Using cullet (recycled glass) significantly lowers emissions, but while this helps, it is not the complete solution.
Supply chain emissions are another critical factor. The transportation of glass, particularly imports, adds to the overall carbon footprint. Encouragingly, some manufacturers are working on Environmental Product Declarations (EPDs) to provide transparent data on embodied carbon, allowing the industry to make informed choices.
More localised supply chains could also help reduce emissions while supporting UK-based production.
For installers and fabricators, sustainability-conscious choices matter. It’s not just about the glass itself – frames, sealants, and fixings all contribute to a project’s total carbon footprint.
Materials like aluminium, PVC-U, and timber have different environmental impacts depending on their sourcing and manufacturing processes. Choosing suppliers that prioritise lower-carbon production methods will help businesses align with sustainability goals.
Another way to lower embodied carbon is by ensuring glazing products last as long as possible. Durability, quality installation, and proper maintenance extend service life, reducing the frequency of replacements and lowering environmental impact. High-performance glazing not only benefits customers through energy savings but also minimises waste over time.
From a business perspective, sustainability is becoming a key differentiator. More homeowners and developers are considering carbon footprints when choosing products, and businesses that can demonstrate commitment to sustainability gain an environmental and hopefully competitive edge.
Certass members have told me how valuable sustainability credentials have been in marketing their businesses and attracting more environmentally conscious customers.
Innovation is playing a key role in reducing embodied carbon. Manufacturers are developing lower-carbon glass, investing in alternative fuels, and introducing advanced coatings that improve performance without increasing emissions.
Digital tools now help specifiers assess the environmental impact of different glazing options, making it easier to choose lower-carbon solutions.
As Chair of Certass and the National Home Improvement Council (NHIC), I see first-hand how sustainability is shaping industry discussions. The glazing sector is making progress, but continued transparency, innovation, and collaboration across the supply chain are essential. By reducing energy-intensive manufacturing, prioritising sustainable materials, and maximising product lifespan, we can make a meaningful contribution to the UK’s carbon reduction targets.
The transition to a lower-carbon glazing industry requires action from manufacturers, installers, and the wider supply chain. By embracing sustainability not as a challenge but as an opportunity, the industry can lead the way in responsible building practices. The decisions we make today will define the impact we have tomorrow, ensuring that glazing remains a key player in creating a greener built environment.