Crafting bespoke windows for over 40 years
London Box Sash is a family business grounded in traditional values and a genuine passion for quality craftsmanship and joinery.
Expertly Handcrafting Sash Windows in London for Over 40 years
London Box Sash Windows is a family run business specialising in high-quality timber sash windows in London. We are committed to providing our customers with exceptional products and service, with a reputation for craftsmanship and quality.
For over four decades, we have been handcrafting custom-made double-glazed sash windows to meet the specific needs of our customers. Our skilled artisans use only the finest materials and our windows are built to the highest standards.

Family owned
From humble beginnings it all started with a wall
Engineer John Ellis founded our company in 1980 with a passion for woodwork. He used his knowledge and experience to create high-quality double-glazed timber sash windows and doors. We have grown over the years, but we remain committed to the same high standards of excellence.

Locally made
Timber Windows & Doors Locally made in London
London Box Sash Windows has been making sash windows in London since 1980. We reduce our environmental impact by installing 95% of our sash windows within 10 miles of our workshop. This helps to reduce our carbon emissions and traffic congestion, and it also supports local businesses and communities.
Bespoke windows
London’s Double-Glazed Sash Window Specialist
LBSW provides high-quality timber double-glazed sash windows in London. We commit to providing exceptional engineering and service to our customers. Our reputation for craftsmanship and quality is second to none.
We build our windows with the finest materials, so they are built to last. We offer a wide range of styles and finishes to choose from, so you can find the perfect window to match your home.
If you are looking for high-quality timber windows in London or Surrey, look no further than London Box Sash Windows. We are the experts in sash window installation and we are committed to providing our customers with the best possible experience.

Our portfolio
Our Portfolio
Discover the quality and craftsmanship of LBSW – browse our timber window projects in London and surrounding areas.
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