Bespoke sash windows in Forest Hill

Replacement sash windows and wooden sliding sash windows installed in Forest Hill, Sydenham and nearby areas

Installing Sash Windows In Forest Hill since 1980!

London Box Sash Windows is your go-to local expert for sash and replacement sash windows. We specialise in crafting bespoke sash windows using premium Accoya wood and A-rated double glazing. Our sash windows blend traditional elegance with modern energy efficiency and long-lasting durability.

Accoya wood, known for its sustainability and resistance to rot, decay, and warping, is the ideal material for sash windows. Combined with high-performance double glazing, our box sash windows offer outstanding insulation, helping to lower energy bills while maintaining timeless charm.

Our sash window team is highly rated on Google reviews and has received top feedback on Which? Trusted Traders, where we have been members since 2011.

One recent customer said:

Very efficient local team, first to book appointment and good contact from Judith in the office. Very thorough presentation from Jake and ability to offer a discount for speedy installation. Andy installed windows and he was professional & friendly. A very clean and methodical approach. They also have an after service care should anything happen which is very reassuring .I have already recommended them to two friends of mine.

All our sash window products are made locally at our London factory near Wimbledon, with 90 per cent of installations within eight miles of production, supporting the community and reducing our environmental impact.

Visit our showroom to explore our sash windows and get expert advice from our knowledgeable team to find the perfect match for your home.

What makes our Sydenham sash window company different?

At London Box Sash, we are passionate about preserving the timeless beauty of sash windows while enhancing your home with modern products. Our skilled team focuses on using the highest quality materials and providing flawless sliding sash window installations that respect the traditional aesthetics of your property. This dedication to craftsmanship and attention to detail has made our services highly sought after and widely recommended.

John Ellis founded our first workshop in 1980, and since then, we have proudly specialised in crafting double-glazed sash windows and doors designed for lasting durability.

With a commitment to traditional craftsmanship and modern innovation, we have grown steadily over the decades. By continually investing in state-of-the-art machinery and refining our techniques, we ensure that every product we create meets the highest quality standards, blending timeless aesthetics with superior performance for homes across the region.

We take the time to explain the intricacies of sash windows, from their history to their functional benefits, ensuring you are fully informed at every step. Whether you are restoring an older property or adding character to a new build, our team is committed to helping your home find its perfect style.

Another client said:

I was very happy with the bespoke casement window they installed in my property. The company also agreed to repair it promptly after a number of years. London box sash install high quality timber windows and seem to care about their customers.

For images of our recent sash window installation projects, please check out our portfolio.

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We fit Accoya sash windows and wooden sash windows in Forest Hill, SE23

Forest Hill in South-East London is known for its charming, tree-lined streets and beautifully preserved period properties, many of which feature classic sash windows integral to their architectural character.

From Georgian townhouses to Victorian terraces, these homes reflect a timeless elegance that makes Forest Hill a sought-after area for homeowners. However, due to the age of many of these properties, original sash windows may have become worn or inefficient over time, leading to drafts, condensation, or difficulty in operation. R

Replacing sash windows with high-quality, energy-efficient replicas can enhance the comfort and aesthetic appeal of these heritage homes. Accoya wood undergoes an innovative acetylation process, making it exceptionally durable and resistant to decay, rot, and insects. This increased lifespan is complemented by its remarkable dimensional stability, ensuring smooth operation and a longer life.

Accoya’s low maintenance is a key benefit, as its reduced water absorption extends the life of finishes. Its thermal insulation properties improve energy efficiency, making it an eco-friendly option that can lower energy costs. Accoya wood also supports sustainability, offering both the environmental advantages of softwoods and the durability of hardwoods, earning C2C Gold certification.

Forest Hill A+ rated sliding sash window installation

Double-glazed sash windows can significantly enhance your home’s energy efficiency. According to the Energy Saving Trust, installing A-rated double-glazed windows in a single-glazed semi-detached home can save homeowners around £195 per year.

The insulated air space between the glass panes in double or triple glazing helps reduce heat transfer by slowing down convection and conduction, keeping your home warmer for longer and lowering heating costs, making it a smart investment for energy-conscious homeowners.

Please see our blog: How long do double glazed windows last?

Matthew Carter

I’ve had 4 windows done by London Box Sash Windows now and every time the entire process from quote to installation is so smooth and stress free that I never bother to contact anyone else.The final windows are great quality and beautiful to look at and the work is always done in the timeframe agreed with the installations always carried out by very friendly and professional people.

Jody Torode

We are a returning customer of London box sash windows. Initially we went with them as they were the cheapest quotes however when we needed other windows to be replaced we didn’t approach any other company, we were so happy with the job they did the first time we wanted to use them again.I was fully informed about what to expect, given clear time scales and they were super helpful in providing information to support our planning application.There was a slight hiccup with the window not being quite right however this was resolved with no issue at all, another window was made and fitted within a few weeks.The fitters are really friendly, work hard and clean. They do an excellent job and I have no complaints what so ever!The whole service from start to finish has been really positive.

Jalon Quinn

All round excellent service from start to finish. Polite, efficient, took care with other parts of the property and cleaned up better than I could have done. Not the cheapest but worth the investment.

Sophie Rushton-Smith

Excellent team, really helpful. The new windows fit perfectly. No draughts, easy to open and close and high quality fittings. So good, we keep going back and have changed them all.

Joseph Webb

Had a set of windows fitted in two rooms, replacing old single glazed windows with new double glazed sash windows. The new windows are a marked improvement and are keeping the house much warmer and better insulated all round. Very professional all round and easy to deal with on fitting timeframes – super speedy fitting too!

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!

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

Beckenham
Catford
Dulwich
Forest Hill
Honor Oak Park
Lewisham
Norwood

Would you like a quote for sash windows or casement window installation Forest Hill? Call London Box Sash now

For an estimate for casement windows or replacement sash windows near you, please call [telme] or email [emailme].

Call our team for sash windows Putney.