Glass Times talks to Roseview’s Mike Bygrave about how sash windows and secondary glazing give installers the tools to win heritage work.

Glass Times (GT): Heritage projects are often seen as tricky. Where do sash windows fit into that?
Mike Bygrave (MB): Heritage jobs can be complex. They often involve planners, conservation officers and detail-oriented customers that can­ test installers’ experience and patience. But they’re also some of the most rewarding projects, both financially and professionally.

At Roseview, sash windows aren’t a sideline; they’re what we do. Ultimate Rose, for example, is designed specifically for authenticity. It’s been continuously refined to look like timber, down to the smallest detail. That is why it’s regularly used in conservation areas. For installers that means less pushback from planners, less time justifying the spec, and more chance of getting the job over the line.

GT: How does that benefit the installer on site?
MB: It’s about confidence and efficiency. If you know you’re fitting windows that satisfy the brief, you’re not fighting an uphill battle. Furthermore, Ultimate Rose installs like a modern window, so you’re not wrestling with the compromises of forcing standard windows into heritage projects.

Then there’s the practical side. Because we foil in-house, including matching trims, installers can get everything in one order, on one delivery. That avoids the delays and hassle of sourcing trims separately. Small things like that make a big difference when you’re on site and the clock is ticking.

GT: What about listed buildings, where restrictions are even tighter?
MB: That’s where secondary glazing comes in. With listed properties you can’t change the external appearance, so secondary is the most viable way to improve performance. Our Incarnation range is designed for exactly that; discreet units that sit alongside the original windows without affecting the outside look.

For installers, secondary glazing opens up jobs you might otherwise walk away from. We’ve seen it used successfully in listed buildings, but also in bigger commercial-style projects such as hotels, office conversions and schools. With secondary glazing those jobs are attractive because they’re efficient, the margins are good, and they attract less competition.

GT: So, sash windows for conservation areas, secondary glazing for listed; is it that simple?
MB: Not at all. Secondary glazing has a role beyond listed buildings. If a developer wants to keep original windows while hitting improved performance requirements, secondary is a cost-effective solution. On large projects in particular, the numbers can stack up more favourably than full replacement.

Likewise, replacement sash windows are usually the better choice for non-listed buildings, because they deliver authenticity alongside modern performance, convenience and low maintenance. The key is being able to offer both, so you’ve got the right tool for the job whichever way it goes.

GT: Roseview has a reputation as a heritage specialist. How does that help installers?
MB: Experience is the biggest differentiator. We’ve been focused on sash windows for almost 50 years, and secondary glazing is part of the same heritage DNA. That means we’ve come across just about every conservation or heritage challenge you can imagine.

From an installer’s point of view, that matters. You’re not just buying windows; you’re buying into the expertise and support that comes with them. We can help with technical details for planners, provide marketing support to help win jobs, and give advice on the fitting challenges that are unique to heritage projects. It’s about making those projects less stressful, more profitable, and ultimately more successful.

GT: Finally, how do you see the heritage market developing?
MB: Demand isn’t going away. Conservation areas are expanding, homeowners increasingly want character, and developers are looking to differentiate. For installers, that means heritage projects will continue to be a rich source of opportunity.

When you have authentic sash windows and secondary glazing in your portfolio, backed by a manufacturer who lives and breathes this sector, you’re in a strong position. That’s exactly where we