Golden Ratio Sash Window & Door Installers London

Golden Ratio Sash Windows & Doors is London’s premier specialist in the restoration, manufacture, and installation of traditional timber windows. From our local workshop, our time-served craftsmen use traditional joinery methods and premium materials like Accoya® to faithfully replicate original features while enhancing energy efficiency. We specialize in bespoke double-glazed sash windows, casement windows, and elegant French doors tailored to period properties. Our services include professional draught-proofing, timber repair, and full window replacements across London. With a 10-year guarantee and a commitment to punctuality and craftsmanship, we help preserve your home’s heritage while improving comfort and value.