LONDON TIMBER SPECIALISTS
Wooden 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.
- Bespoke timber matched to your original windows | profiles, glazing bars and proportions replicated exactly
- Conservation area and listed building experience | we know what's permitted and can advise before you commit
- Double or triple glazing fitted as standard | period looks, modern thermal performance
- Full removal and disposal included | old frames out, site left clean, no hidden extras
- Free home visit and written quote | no call centres, no pressure, no obligation
- ★★★★★ Google Reviews
- 9.98/10 Checkatrade
- 10+ Years Experience
- Family Run Business
- Free Estimates & Advice
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.
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
When replacing sash windows, the quality of the installation matters just as much as the windows themselves. We focus on getting the details right, from careful removal to clean, precise fitting, so your new windows perform exactly as they should from day one.
Not 100% sure if your existing timber sash windows need replacing or just some expert attention?
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.
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.
Get in touch
- 07546 408060
- 07546 408060
- klisjoineryandcarpentry@gmail.com
- Serving central & west London
Ready to get started with bespoke timber sash window replacements for your London home?
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.
2. Can you match the style and proportions of my original period windows?
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.
3. Are your replacement sash windows available with double glazing?
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.
4. Do you work in conservation areas or on listed buildings?
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.
5. How long does sash window replacement take?
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.
6. What timber do you use and how long will it last?
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.
7. Do you take away the old windows and leave the site clean?
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.
8. How much does sash window replacement cost?
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.