Menu
London's trusted window installation service — call us for a free site survey.
Get a quote
We specialise in the repair, restoration, and replacement of traditional timber sash windows across Islington. Our master joiners blend traditional craftsmanship with modern techniques to preserve your home's character and improve thermal efficiency.
No obligation · Free site survey · Reply within hours
Golden Ratio Joinery Ltd provides expert Sash Window Replacements for period homes across Islington (N1, N5 & N7).
Living in an Islington period property is wonderful — dealing with rotten sills, fierce draughts and single-pane glass is not. When repair is no longer enough to save your frames, we build complete bespoke replacements. As a workshop based in N7, we know the borough intimately, from the classic Georgian townhouses of Canonbury to the tall Victorian terraces of Barnsbury.
We never fit plastic frames. Our joiners build everything to order in sustainably sourced timber, copying your existing glazing bars, horns and architraves exactly — with modern performance built in:
Matching sight lines and mouldings so your new windows are indistinguishable from the originals from the street.
Engineered to stay straight and rot-free for decades, finished in a factory-applied microporous paint of your colour.
21st-century warmth and noise reduction without upsetting the local conservation office.
Most of Islington's streets fall within conservation areas where replacements must match the original design. We supply conservation-grade timber windows that satisfy the council and handle the detailing for you, so your project runs smoothly and to current building regulations with full FENSA certification.
It is a big decision to pull out old joinery — if your windows are sound but tired, ask about restoration or a straightforward repair first. See our recent work in the gallery, check our price guide, or view all areas we cover.
Book a free, no-obligation site survey with our FENSA-registered joiners. We will assess your windows, explain your options honestly, and give you a transparent written quote. Call 020 3488 1695 or request a callback today.
We also provide expert sash window replacements across these neighbouring London areas:
A selection of recent sash window repairs, restorations and installations completed for homeowners across Islington and North London.
Finsbury Park
"Saved our original Victorian windows when others said replace. Beautiful workmanship — our sash windows look brand new."
Stoke Newington
"Draughts completely gone. Warm house for the first time in years. Fair price and they clearly know period properties inside out."
Central London
"They completely replaced two windows in our Edwardian home. Friendly, communicative and done quickly — in just 2 days."
North London
"The detailing is very well done and accentuates the property nicely. The whole front of the house looks much better as a result."
Queens Park
"The window is perfect. I couldn't be happier."
Yes. We regularly carry out sash window repair and restoration services in Islington and all surrounding boroughs. We offer free site surveys for all local residents.
Yes, absolutely. We specialise in retrofitting slimline double-glazed units into original timber sash windows. This means you don't have to rip out the entire window box, saving money and preserving the historical character of your property.
Costs vary depending on the extent of the damage (e.g., rotten sills vs simple broken cords). However, repairing is almost always significantly cheaper than a full replacement. We provide completely transparent, itemised quotes after a free survey.
Stop the draughts and start saving on energy bills. We offer a free, no-obligation survey and quote for all window upgrades across London.
218 Hornsey Road, London, N7 7LL
Fill in the form and we'll get back to you within one business day.
