Location: Hobury Street, Chelsea, London SW10
Property Type: Georgian Townhouse
Homeowner: Amy and Richard
Product Installed: New timber double-glazed sash windows
When Amy and Richard moved from Wimbledon to their Georgian townhouse on Hobury Street in Chelsea in 2025, they inherited a problem that’s more common than most homeowners realise. A few years before they bought the house, builders had carried out a full refurbishment, including new windows. On paper, the windows had been “done.” In practice, they were terrible from the start, and it’s the kind of sash window replacement work we’re called out to do in conservation areas across London regularly.
The builders had fitted double-glazed sash windows, but the proportions were off. The rail and stile widths, the glazing bars- none of it matched the character of a Georgian townhouse in a conservation area like this part of Chelsea, SW10. It’s a mistake we see often. A builder brings in a local joinery firm to knock out replacement sashes for a quick turnaround, and the windows that go in simply don’t look like they belong to the period of the house.
Beyond how they looked, the windows weren’t performing either. They let in draughts, they rattled in their frames, and despite being double-glazed, they had already started to rot. No draught proofing had been carried out, so the double glazing was doing very little of the job it was meant to do. By the time Amy and Richard moved in, most of the sashes had stopped opening and closing properly altogether.
We were brought in to replace the sashes with new timber double glazed box sash windows, built to the proportions a Georgian townhouse in Chelsea like this should actually have. That means glazing bars sized and positioned the way they’d have been originally, not an approximation.
The work was carried out in two phases. In 2025, we replaced sashes in seven windows across the house. In 2026, we went back and replaced a further four box sash windows. Both phases used the same specification: timber, double-glazed, and built with glazing bar proportions that are authentic to the period rather than a generic modern take on a sash window.
Amy and Richard were living in the house throughout both phases of work, and some of the rooms we were working in had already been freshly decorated. We sheeted up floors and furniture before starting, and where a room had just been finished, we made sure the windows went in without disturbing the decoration around them. The first phase, covering seven windows, took just over a week. The second phase, four windows, took four days.
SW10 in Chelsea is a conservation area, so getting the proportions and detailing right isn’t optional. It’s the difference between windows that look like they’ve always been there and windows that mark the house out as having had cheap replacements at some point. We build every sash to match what the original joiner would have made, just with modern double glazing behind it.
The most immediate change for Amy and Richard is a simple one. The windows open and close properly now, which the previous ones never did. The rooms are warmer, the rattles and drafts are gone, and the house is noticeably quieter.
Just as importantly, the windows now look like Chelsea Georgian windows again. The proportions match the house, the glazing bars sit where they should, and the sash windows read as part of the property rather than something bolted on. Amy and Richard have left us a five-star Google review for the work.
If your period property has had windows fitted that never quite looked right, or that were meant to be double glazed but still let in the cold, it’s worth having a proper look at what’s actually behind them. Get in touch with Novells for a quote, and we’ll tell you honestly what we find.
Double glazing cannot perform properly if the sashes are poorly fitted or there is no effective draught proofing. Gaps around the windows can allow cold air into the room and cause the sashes to rattle. In this Chelsea property, the existing windows were double-glazed but remained cold, noisy and difficult to use.
Yes. New timber sashes can be made with glazing bars, rails and stiles that reflect the original proportions of the property. This is particularly important for Georgian homes and properties in conservation areas, where generic replacement windows can look noticeably out of place.
Properly fitted double glazed timber sash windows can reduce draughts, rattling and outside noise while helping rooms retain more heat. Following the replacement work at this Chelsea townhouse, the rooms felt warmer and quieter, and the windows opened and closed correctly.
In most cases, yes. Amy and Richard remained in their home throughout both phases of this project. We protected the floors, furniture and freshly decorated areas before beginning. Seven windows took just over a week to complete, while the second phase of four windows took four days.
As Co-founder of Novells Sash Windows, Philip has spent over 20 years perfecting the craft of designing, supplying, and fitting luxury wooden double-glazed box sash windows.
A family-run business led by Philip and his wife Nicola, Novells has fitted thousands of wooden windows across London and Surrey, with clients including Vivienne Westwood and the Victoria & Albert Museum.
