KLIS JOINERY & CARPENTRY LTD
LONDON TIMBER SPECIALISTS

Timber Sash Window Replacement in London

Bespoke timber replacements crafted to match your home’s character. Double glazed, draught-free, built to last. Projects completed across all price-points.

Klis Joinery & Carpentry

Helping London homeowners design and craft the perfect replacement sash windows for heritage and contemporary homes. 

Not every timber window can be repaired. When decay is advanced, frames no longer seal properly, or the sashes stop working as they should, full replacement is often the most practical long-term solution. We manufacture bespoke timber sash window replacements that retain the character of your home while solving the everyday problems old windows cause.

Call us if you’re experiencing:

When timber deterioration goes too far, repairs often become short-lived and poor value. Soft, rotten, warped, or structurally weakened frames can affect both appearance and performance, making full replacement the better long-term option.

Older single-glazed sash windows often let in cold air, outside noise, and unwanted moisture. If your home feels uncomfortable near the windows or your heating struggles to keep up, replacement can dramatically improve warmth, insulation, and day-to-day comfort.

 

If your sash windows are jammed shut, difficult to lift, or no longer close and seal properly, they are no longer functioning as they should. In many cases, especially with older or heavily worn units, replacement is the most reliable way to restore smooth operation.

1. Rotting or damaged timber frames

When timber deterioration goes too far, repairs often become short-lived and poor value. Soft, rotten, warped, or structurally weakened frames can affect both appearance and performance, making full replacement the better long-term option.

2. Windows responsible for Draughts, noise and heat loss

Older single-glazed sash windows often let in cold air, outside noise, and unwanted moisture. If your home feels uncomfortable near the windows or your heating struggles to keep up, replacement can dramatically improve warmth, insulation, and day-to-day comfort.

3. Broken sash cords and seized windows

If your sash windows are jammed shut, difficult to lift, or no longer close and seal properly, they are no longer functioning as they should. In many cases, especially with older or heavily worn units, replacement is the most reliable way to restore smooth operation.

Klis Joinery & Carpentry
Trusted for Timber Window Replacements Across the Capital

Not 100% sure if your existing timber sash windows need replacing or just some expert attention?

Reach out to Klis Joinery & Carpentry for an obligation-free discussion and a complimentary at-home consultation to discuss your timber sash window needs. We’re not pushy, and we’re not a hard-sell. We’re here to offer sound, reputable advice that allows you to make an informed decision!

Trusted by homeowners across London

We’re proud of our consistently high ratings on Checkatrade and Google. Our work is regularly praised for reliability, workmanship, and attention to detail — not just the finished result, but the way we carry out the job from start to finish.

Straightforward advice you can rely on

We’ll assess your windows honestly and explain your options clearly. If replacement is the right solution, we’ll guide you through it. If not, we’ll tell you — no pressure, no upselling.

Experienced with period and modern homes

From traditional sash windows in older properties to newer installations, we understand how to fit replacement windows so they look right and perform properly within the context of your home.

Clean, careful installation with no unnecessary disruption

We take care when removing old frames and fitting new ones, protecting surrounding finishes and leaving your home clean and tidy. No rushed jobs, no mess left behind.

Not 100% sure if your existing timber sash windows need replacing or just some expert attention?

Reach out to Klis Joinery & Carpentry for an obligation-free discussion and a complimentary at-home consultation to discuss your timber sash window needs.

We’re not pushy, and we’re not a hard-sell. We’re here to offer sound, reputable advice that allows you to make an informed decision!

Written, Fixed Quotes

Family-run business

Box & Spiral Sash windows

Careful & Tidy repairs

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Devis Drini profile picture
Devis Drini
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Excellent sash window replacement in Fulham. The team was professional, punctual, and the craftsmanship was outstanding. The new timber sash windows look beautiful, operate smoothly, and have made a noticeable difference to noise reduction. Highly recommend Klis Joinery & Carpentry Ltd for anyone in Fulham looking for quality sash windows.
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Liv Walker profile picture
Liv Walker
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Sash window repairs Fulham - excellent service, came out and fixed my window and had the job complete in under an hour! Super friendly and helpful, would definitely recommend! :)
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Geron Guraj profile picture
Geron Guraj
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Klis did a full overhaul on my sash windows in Hampstead, freshly painted, and they replaced the cords too. The house feels just right now, and the windows are back to their best.
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Xhuljo Kamberi profile picture
Xhuljo Kamberi
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A great job from Klis Sash Windows. The windows are much more comfortable now and the safety restrictors were exactly what we wanted. Turned up when they said they would and got everything done properly.
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Alie profile picture
Alie
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Klis Sash Windows replaced our old sash windows in Richmond Hill and did an excellent job. The workmanship was first class, communication was great, and everything was completed exactly as promised. We're delighted with the new windows and would happily recommend them.
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K K profile picture
K K
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Had sash windows replaced at property in Chelsea, excellent service and quality Highly recommend
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David Gasson profile picture
David Gasson
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Did 1 sash 1 window in our Clapham house as a test and really happy. Great service, good price and will happily do tge other windows with Klis.
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Stelios Fiakkas profile picture
Stelios Fiakkas
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Klis Sash Windows recently replaced our original timber bay windows in Chelsea SW3. The new bespoke hardwood sash windows match the character of the property perfectly while improving insulation and reducing draughts. The workmanship, attention to detail and finish were excellent throughout. We are delighted with the result and would highly recommend Klis Sash Windows for bay window replacement in Chelsea.
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Ryan Çetin profile picture
Ryan Çetin
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I recently had my Victorian wooden sash windows replaced by Klis Sash Windows and am delighted with the result. The new timber sash windows look beautiful, with high-quality traditional ironmongery and excellent attention to detail. The team was professional, tidy, and completed the installation to a very high standard. Highly recommended for anyone looking for sash window replacement in the Fulham/SW London Area.
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Ann-Isabell Schulz profile picture
Ann-Isabell Schulz
Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google.
I had a sash window replacement in Fulham. I was contacted immediately and had the windows fixed the next day. Provided a very friendly and efficient service. Highly recommend.

IMAGE SLIDERS

Recent Projects & Our Workshop

OUR PROCESS

THREE STEPS TO NEW SASH WINDOWS

01 | Free home visit & survey

We come to you, assess your windows in person and provide a clear written quote. No call centres, no pressure, no obligation.

02 | Bespoke windows crafted & fitted

Your replacement sash windows are built to your exact measurements and installed by our team with minimal disruption to your home.

03 | Clean handover & aftercare

Old frames removed, site left spotless, every window tested before we leave. We're on hand if you need us after the job is done.

WHERE WE WORK

Serving homeowners across London

We install replacement sash windows across central and west London. Not sure if we cover your area? Call or message us — we’re happy to advise.

Fulham Camden Hammersmith Hampstead Islington Richmond Westminster Kensington Chelsea Notting Hill Mayfair Battersea Chiswick Wimbledon Clapham Putney Barnes Belgravia Marylebone St John's Wood Primrose Hill Highgate Maida Vale Holland Park Ealing and more

Ready to get started with bespoke timber sash window replacements for your London home?

Reach out to Klis Carpentry and Joinery today for an obligation-free discussion of your needs, or to schedule a complimentary at-home desgin consultation.

FAQs

Your questions about
Sash Window Replacements answered

1. How do I know if my sash windows need replacing rather than repairing?

Repair is usually the right call when the core timber frame is still structurally sound — broken sash cords, minor draughts, rattling and small areas of surface rot can all be fixed without replacing the whole window. Replacement makes more sense when frames have deteriorated beyond repair, when timber has rotted through, or when you want to upgrade to double glazing. We’ll assess your windows honestly during a free home visit and tell you which option is right — we won’t recommend replacement if a repair will do the job.

Yes — this is central to what we do. We replicate original profiles, glazing bar layouts, meeting rail positions and proportions exactly so that replacement windows are indistinguishable from the originals. Whether you have Victorian two-over-two sashes, Edwardian six-over-six, or something more unusual, we work from your existing windows to ensure the replacements are a precise match.

Yes. All our replacement sash windows are available with modern sealed double-glazed units fitted into traditional timber frames. This gives you significantly better thermal performance and noise reduction while keeping the period appearance intact. Triple glazing is also available for properties on particularly busy roads or where maximum insulation is a priority.

Yes, we have extensive experience working within conservation area guidelines and on listed properties across London. Permitted development rules vary by borough and listing status — we can advise you on what’s likely to be approved before you commit to anything, and we’re familiar with the typical requirements around timber frames, slim-profile double glazing, and matching original designs.

For a typical residential job — two to four windows — we’d normally complete the work in one to two days after the windows have been crafted. Larger projects covering a full property are planned carefully to minimise the time any opening is exposed. We’ll give you a clear timeline when we visit, and we keep disruption to a minimum throughout.

We use high-quality, sustainably sourced African Sapele hardwood selected for stability and longevity. All timber is treated before installation to resist moisture, rot and warping. Properly maintained — painted every five to seven years — good quality timber sash windows will last decades. We can advise on the best finish and maintenance routine when the job is done.

Yes, always. Removal and full disposal of old frames is included as standard — there are no hidden charges for this. We protect surrounding walls, floors and finishes during installation, and we leave every work area clean and tidy before we go. We also test every window before we leave to make sure it opens, closes and seals correctly.

Costs vary depending on window size, number of windows, glazing specification and any complexity around period matching or conservation requirements. As a general guide, most replacement sash windows start from around £1,200 per window fully installed, depending on the size and configuration. The best way to get an accurate figure is a free home visit — we’ll assess your windows, discuss your requirements and provide a detailed written quote with no obligation to proceed.