Answer extracted from the Glazing Insider podcast — listen to the full episode below.
What is the biggest change in the fenestration industry over the past 40 years?
The biggest change in fenestration over four decades has been driven by standards and regulations pushing product quality much higher. Products from the 1980s were basic and insecure, but today all systems meet requirements of PAS24 and Secure by Design when assembled correctly, giving consumers far better products in both security and energy performance.
From Trial and Error to Certified Excellence
When John Warburton entered the fenestration industry in the mid-1980s at a small PVC window fabricator in Lancashire, the sector operated in a completely different regulatory landscape. There were no technical manuals, no support from system houses, and manufacturers learned by trial and error—building conservatories and making windows with no concept of how they should actually be constructed, then adapting as experience accumulated.
The products that came out of that era reflected this ad-hoc approach: basic, unrefined, and with minimal security considerations. As Warburton explains in the episode, the transformation accelerated when the industry began to standardize. Standards such as PAS24 and Secure by Design emerged as the benchmark, requiring manufacturers to prove their products met specific performance criteria before they could be sold to consumers.
Today, when these standards are applied correctly during assembly, every window and door entering the market offers a level of security and energy efficiency that would have been unthinkable in the 1980s. This regulatory shift has fundamentally reshaped how manufacturers design, test, and certify their products—moving the entire industry away from improvisation and toward measurable, auditable compliance.
The role of certification bodies like ER Certification became central to this transformation, ensuring that products conform to these standards before they reach the market. This shift from unregulated manufacturing to standardized, certified production represents the most profound change the fenestration sector has experienced in four decades.
"I think we provide a very, very good service. Customers seem to appreciate what we do. I think we're firm but fair."
John Warburton — Managing Director, ER Certification Ltd. With over 40 years of experience in fenestration, Warburton has held roles across manufacturing, sales, product development, and technical management at companies including Profile 22, Commolin, Vika, and Epwin. He joined the Building Research Establishment (BRE) in Watford to help establish certification schemes for windows and doors, before purchasing and managing ER Certification Ltd.
A deeper look at how certification testing actually works and what failure rates reveal about industry compliance is covered in more detail in the full episode, where Warburton discusses real-world testing outcomes and what they mean for manufacturers aiming to meet these benchmarks.
See also
How did early experience in PVC window manufacturing during the 1980s shape understanding of fenestration production?
John started at a small fabricator in Lancashire in the mid-1980s making PVC windows during the early days of PVC. He spent his first 18 months learning manufacturing from start to finish, progressing through order processing, purchasing, and layout work.
What is the scope of machinery representation at Fit Show 2025?
Fit Show 2025 has the biggest representative display of machinery that has ever been shown, which is massively important for the industry to see the latest equipment and innovations available.
When is Fit Show scheduled for 2027 and what is the preparation timeline?
Fit Show 2027 is scheduled for the 18th to the 20th of May 2027. Although this seems a long way away, it takes every ounce of energy to start the journey and begin preparations.