Secondary glazing is seeing a marked rise in popularity across the UK, as more homeowners seek practical ways to make their homes warmer and quieter—without altering the charm of their original windows.
This technique involves installing a slim glass panel on the inside of an existing window, providing a noticeable upgrade in both insulation and noise control. It is especially beneficial for period properties and listed buildings, where traditional double glazing is often restricted by planning regulations.
“In the last couple of years, interest in secondary glazing has really taken off,” says Colin, founder of Colin’s Sash Windows, a specialist provider of timber sash windows and secondary glazing serving customers nationwide.
“It’s discreet, it’s effective, and it’s often half the cost of full window replacements.”
The demand for better-performing windows is timely. According to GGF and British Glass (2023), around 80 million windows in UK homes still fall short of current energy standards. The English Housing Survey reports that one in ten properties still has single glazing—a major source of heat loss, accounting for up to 20% of thermal inefficiency (Energy Saving Trust).
Secondary glazing also serves as a powerful noise barrier. Colin’s Sash Windows notes that it can reduce outside noise levels by as much as 80%, making it an attractive choice for homes near busy roads, railways, or flight paths. In many such areas, installations are supported by grants from local councils or airport-funded schemes.
With nearly 3 million UK homes still using single-glazed windows—many of them older or character-rich buildings—the need for retrofit-friendly solutions is clear.
The rental sector is also feeling the impact.
“We often hear from landlords who are losing tenants because flats are too cold or too noisy,” Colin said. “Secondary glazing is a cost-effective way to fix both problems, protect rental income, and improve the property’s EPC rating.”
With tighter energy efficiency rules expected in the near future, particularly for rental properties, upgrading windows is becoming an essential part of long-term property planning. Secondary glazing offers a practical way to raise EPC scores without extensive renovations.
In cities like London, demand for secondary glazing is growing rapidly, particularly in conservation areas where window replacements must meet strict heritage guidelines. Historic centres such as Bath, York, and Edinburgh are also seeing an uptick in installations as homeowners look to balance comfort and compliance.
“Secondary glazing used to be niche, but now it’s becoming mainstream. People want warmer, quieter homes and this is a smart, affordable way to get there,” Colin added.
