Leading company for sash windows Lewisham

A-rated sash windows and Accoya sash windows for energy saving and aesthetics in Lewisham, Hither Green, or nearby areas

London Box Sash Windows is a local, trusted, family-run business with over four decades of experience providing top-quality timber sash and casement windows throughout the London area. Every project is executed with care, ensuring your satisfaction at every step.

We specialise in crafting and installing traditional timber sash and casement windows. We prioritise energy efficiency while maintaining your property’s architectural charm and kerb appeal. Our windows are made from Accoya wood, which is also energy efficient and will save you money on fuel bills.

From designing and crafting bespoke sash windows to expert installation and ongoing replacement services, our specialists handle every aspect of your sash window needs. With a commitment to quality and attention to detail, London Box Sash Windows ensures your home retains its character while benefiting from modern efficiency and craftsmanship you can rely on.

Our dedicated and skilled team takes pride in delivering a helpful, reliable, and professional service you can trust. Whether installing new sash windows or replacing existing ones, we offer customised solutions tailored to your needs at competitive prices.

We take great pride in our trusted relationships with our clients. One recent customer said:

I recently had a new sash window fitted in my living room, and London Box Sash could not have been more helpful. Jake was absolutely brilliant and talked me through all the options and helped me choose what was right for me. The ordering process was simple and the fitting was carried out in one day and I am so happy with the finish. Would definitely recommend – the care and attention to detail is wonderful. Thank you!

Get a sash window quote now by calling 020 8648 4230.

Hither Green Exceptional replacement sliding sash windows & box sash windows installed near you

At London Box Sash Windows, each product is made to order and installed by our in-house specialists. To ensure your satisfaction, all sash window and casement window installations come with a full guarantee, giving you confidence in the durability and quality of our work.

We provide personalised, detailed quotations for every project and are always available to answer your questions. All replacement box sash windows are custom-made and handcrafted, ensuring an authentic and precise reproduction tailored to your home’s needs.

For examples of our recent sash window installations, explore our portfolio.

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Why opt for Accoya sliding sash windows in Lewisham, SE13

Lewisham in South East London is known for its diverse mix of architectural styles. The area features Victorian and Edwardian terraced houses with ornate sash windows and post-war housing developments that add to its varied character. Modern apartment complexes and regenerated spaces are becoming increasingly common, blending contemporary design with the area’s historic charm. Our sliding sash windows can be designed to match properties of all styles and descriptions.

Accoya wood is an engineered timber treated with a patented acetylation process. This process enhances its natural properties to deliver exceptional durability, stability, and resistance to decay. These features make it ideal for modern replica replacement sash windows, blending traditional aesthetics with advanced performance.

Accoya’s durability ensures a lifespan of over 50 years above ground, far surpassing untreated timber and many hardwoods. This makes it highly reliable for external applications. Its dimensional stability prevents swelling, shrinking, or warping.

Accoya’s excellent thermal efficiency improves insulation, reducing energy loss and heating costs. Sourced from FSC®-certified forests and 100% recyclable, Accoya is an eco-friendly choice for sustainability-focused homeowners.

Please see our blog: Maintaining sash windows: Tips for London homeowners.

Lewisham sash window installation: What makes our company special?

Since 1980, London Box Sash Windows has crafted high-quality sash windows that are close to our customers. By installing 95 per cent of our windows within 10 miles of our London workshop, we minimise our environmental impact, reduce carbon emissions, and support local businesses and communities.

Our London workshop specialises in restoring, repairing, and creating sash windows, blending timeless elegance with modern functionality. Located centrally, it serves as a hub for homeowners, professionals, and sash window enthusiasts, offering expert craftsmanship and personalised service to preserve the charm and character of every property.

Michael Gould

Box Sash are a truly exceptional company employing fantastic (considerate, skilled and tidy) craftspeople and a superb customer communications team. We have had a living room bay, a bathroom with two windows, a bedroom with two windows and two other bedrooms done briliiantly. We are very happy with them and we keep coming back for more.

Lottie Birmingham

I recently had a new sash window fitted in my living room and London Box Sash could not have been more helpful.Jake was absolutely brilliant and talked me through all the options and helped me choose what was right for me. The ordering process was simple and the fiting was carried out in one day and I am so happy with the finish.Would definitely recommend – the care and attention to detail is wonderful.Thank you!

Emma V

Thrilled with our 3 new box sash windows. The quality of the windows is excellent and worth every penny. I thought the price was very fair compared to other quotes I received given the quality of the wood that is used, the length of the guarantees and the ease of the company to deal with. The process from start to end has been seamless. Everyone we interacted with was superbly knowledgeable, responsive and helpful – from Harry, the sales person who helped explain all the design considerations and options very clearly, Judith in the office helping getting us booked in and Andy, the fitter. Andy consulted us on any bits where needed explaining clearly the decision that was needed and his work was to an excellent standard and he was very clean and tidy and respectful of our home. He also kindly made the suggestion to ask our decorator to angle the external sills as they were flat so that the water runs off which would help avoid any damp issues and improve longevity. His wealth of experience was very obvious and I was grateful for him sharing these pointers and discussing directly with my decorator – it’s something that would never have crossed my mind without his tip. I thoroughly recommend!

Robert Purdew

Can’t recommend enough.The windows installed seem like they’re a really high quality product. Very good customer service from end to end. They do a really thorough consultation & respond quickly to calls and emails. The day of the installation was easy and the guys who installed were quick and left no dust or mess. Followed up at the end via text, email and a call to check I was happy with the product – highly rate this approach.

Christine Haight

I found London Box Sash Windows through an online search.With my previous company, I did not get any Fensa certificate and the quality of the wood was inferior to the one used by LBSW for similar prices.They offer a 10% discount for their Standby Schedule Saving which gives very good notice for the client as well. I am very pleased with my double glazed window and the people at LBSW are very helpful.Christine Haight

Judy Carlisle

Both salesman and surveyor were straightforward, helpful and answered all questions.Installers were very efficient, worked very hard, cleaning thoroughly.Astonishingly job completed in 6 hours.The only failing was forgetting to move a chest of drawers.Judith was friendly, very helpful and reassuring

Doxy

We are delighted with our new windows. From our initial enquiry onwards everything was dealt with in a thoroughly professional, efficient and respectful way. A special mention of Andy, our fitter, whose craftsmanship and attention to detail was amazing.

Tasha Spencer

Jake provided a great consultation and really listened to my requirements. He was confident, yet gentle with his approach and so knowledgable. I received multiple quotes from providers which honestly felt like a waste of time, as they didn’t seem to listen to my needs of wanting timber only. London Box Sash Windows stood out among them all, especially for their expertise and care in period properties. Really competitive pricing as well! Cannot wait to use and would highly recommend!

Book a sash window survey in any of the nearby locations:-

Cubitt Town
Deptford
Forest Hill
Greenwich
Kidbrooke
Lewisham
Millwall
New Cross
Poplar
Shooters Hill

Would you like a sash windows consultation in Lewisham? Call now

Our sash windows team is here to take your call. Please call 020 8648 4230 or email info@londonboxsash.com.

Do you need sash windows Kingston? Call our local specialists today.