Service
New sash windows London
When a sash window reaches the end of its useful life, a full replacement is often the clearest path to restoring both the appearance and performance of your home. At Repair a Sash, we design and manufacture new timber sash windows built to complement the character of your property – whether that means replicating the slim profiles of a Victorian terrace or the elegant proportions of a Georgian townhouse.
Our work is rooted in London’s period housing stock. From the first survey to the final installation, we focus on getting the details right: the glazing bar profiles, the moulding runs, the hardware, the finish. Whether we are replacing original wooden sash windows or later poor- quality units, new sash windows should look as though they belong – because, done properly, they do.
New sash windows for London period homes
London’s residential streets are defined by their period architecture. Georgian, Victorian, and Edwardian properties each have their own sash window proportions, detailing, and character, and replacing those windows demands a level of care that goes well beyond a standard off-the-shelf product.
Every new sash window we produce is made to match the specific requirements of your property. We work from careful measurements of the existing frames and profile details, ensuring that new windows sit accurately within the opening and reflect the original style of the building. Timber species, moulding profiles, glazing bar widths, and hardware finishes are all considered as part of that process.
For properties in conservation areas, or where the building is listed, replacement requires additional thought. Planning permission or listedbuilding consent may be required, and the specifics will vary depending on your local authority and the nature of your property. We can manufacture heritage sensitive replacements designed to satisfy period-appropriate detailing requirements, and we are happy to advise – but we would always recommend confirming the relevant consents with your local planning authority before work begins.
When new sash windows are the right choice
Not every deteriorating sash window needs to be replaced. In many cases, skilled repair or renovation can extend the life of an original window considerably – and where that is the right call, we will tell you so.
That said, there are circumstances where full replacement is the more practical and cost-effective solution:
- The timber has deteriorated beyond the point where repair offers lasting value
- The existing windows are draughty and inefficient, and no longer performing adequately
- Multiple components need attention simultaneously, making replacement the more economical route
- The homeowner wants a complete visual and performance upgrade rather than a patch repair
- The original windows were poor-quality replacements already worth improving upon
Not sure whether repair or replacement is the better option?
If your windows are broadly sound but suffering from draughts, sticking sashes, or rattling, our Draught Proofing & Renovation service may be a more appropriate and economical starting point. If the existing box frame is in good condition but you want to upgrade to double glazing without a full replacement, our New Double Glazed Sashes service allows new double glazed sashes to be fitted within the retained original frame. And if the windows need specific repairs rather than a full replacement, our Sash Window Repair service covers a wide range of remedial work.
A free survey is the clearest way to understand which route suits your property. We will give you an honest recommendation.
Our services
Renovation on time
and within your budget
Benefits of replacing your wooden sash windows
Comfort and energy efficiency
New timber sash windows, manufactured to modern performance standards, offer a significant improvement over older single-glazed originals. Draught-free sash runs, upgraded seals, and the options of double glazing, slimline double glazing or vacuum glazing can all help reduce heat loss and create a more comfortable interior, while single glazing remains available where a more traditional specification is required – like for listed buildings. For homeowners in older London properties who have long tolerated cold rooms and high heating bills, the difference can be substantial.
Reduced external noise
London is not a quiet city. New sash windows with appropriate glazing can provide a meaningful reduction in external noise – particularly valuable on busier streets or near main roads. This is one of the most commonly cited improvements our customers notice after installation.
Improved security
New sash windows are fitted with secure fastenings and locking mechanisms as standard. Modern sash locks and restrictors offer considerably better security than worn or outdated original hardware, giving homeowners straightforward peace of mind without compromising the traditional appearance of the window.
Long-term value and appearance
A well-made new sash window, installed and finished properly, should last for decades. Beyond the practical benefits, the visual improvement to the property is immediate – new windows transform the exterior of a period home and help protect its long-term value and kerb appeal.
Timber options and finish choices
All of our new sash windows are manufactured in timber, and the choice of species will affect durability, appearance, and finish. We work with four options to suit different requirements and budgets.
Accoya is a modified softwood that has become one of the most widely specified timbers in the joinery industry for external use. Exceptionally stable and highly resistant to rot, it carries an extended guarantee and is an excellent choice for homeowners who want high performance with minimal long-term maintenance.
Red Grandis is a hardwood with a fine, consistent grain and a warm, even tone. It takes paint and stain finishes well and offers excellent durability, making it a strong choice for high-quality joinery where a hardwood character is preferred.
Oak is a classic option with a strong natural grain and excellent longevity. It suits properties where a traditional or natural timber appearance is desired and can be finished in a range of ways.
Engineered Redwood is a practical and cost-effective option for painted finishes. The engineered construction improves dimensional stability compared to solid softwood, making it a reliable choice for standard painted sash windows.
We will advise on the most suitable timber and finish combination for your property during the survey.
Our new sash window process
Free survey and advice
The process begins with a free, no-obligation survey at your property. We assess the existing windows, discuss your requirements, and advise on the most appropriate approach – whether that is full replacement or an alternative service.
Measuring and matching
Where replacement is the right route, we take precise measurements of the existing openings and record the key details of the original windows – profiles, mouldings, sight lines, and hardware – so that new windows can be made to match accurately.
Timber and finish selection
We guide you through the timber options and finish choices, helping you select the combination that best suits your property and budget.
Manufacture
Your windows are manufactured to the agreed specification. We do not use generic off-the-shelf units – each window is made for your property.
Installation
Our installers fit the new sash windows carefully, ensuring they run smoothly, seal correctly, and sit accurately within the opening.
Final checks and guarantee
Once installed, we carry out final checks to confirm everything is operating as it should. All our work is fully guaranteed.
FAQs about new sash windows in London
For most London period homeowners, yes. New windows made to match the original character
of the property improve appearance, comfort, energy efficiency, security, and noise reduction
simultaneously – and a well-made timber sash window will last for many decades with
appropriate maintenance.
Yes. We work from careful measurements and profiles of your existing windows to ensure
replacements reflect the original proportions, moulding details, and glazing bar configuration.
The aim is always for new windows to look as though they have always been part of the
building.
We manufacture new timber sash windows in Accoya, Red Grandis, Oak, and Engineered
Redwood. Each has different characteristics in terms of durability, appearance, and cost. We will
advise on the most suitable choice during your free survey. For larger projects we can
manufacture the sash windows in any timber of your choice.
Yes. New windows manufactured to current standards – with draught-free running, upgraded
seals, and the options of double glazing, slimline double glazing or vacuum glazing – can
significantly reduce heat loss compared to older single-glazed windows, while single glazing
remains available where it is more appropriate to the property. Many homeowners notice a
meaningful improvement in warmth and a reduction in heating costs.
Yes, particularly with double glazed units and appropriate glass configuration for noise
reduction. Improved noise reduction is one of the most valued benefits our customers report,
especially those on busier London streets.
It depends on the condition of your existing windows. If the timber is broadly sound and the
issues are limited, repair or draught-proofing renovation may be the better call. If the windows
are heavily deteriorated or no longer worth repairing, full replacement is likely to give better
long-term value. A free survey is the most reliable way to get a straight answer for your specific
situation.
Listed building consent or planning permission may be required before replacing windows on a
listed building, or in some conservation areas. Requirements vary by property and local
authority. We can manufacture heritage-appropriate replacements designed to meet period
detailing requirements, and we are happy to advise – but we recommend confirming the relevant
consents with your local planning authority before work begins.
Related timber services for your home
Depending on your windows and the wider scope of your project, you may also be interested in:
- Casement windows – for homes where a different timber window style is more suitable.
- Doors – for homeowners planning wider timber joinery improvements alongside their windows.
- Bespoke doors & windows – for special projects that call for something outside our standard range.
Why homeowners in London choose Repair a Sash
We work specifically in the London market, and the majority of our projects are in period properties. That focus matters. The requirements of a Victorian terrace in Islington or an Edwardian semi in Chiswick are not the same as a modern new-build, and we do not treat them as if they were.
Our approach is built on honest advice, careful measurement, and craftsmanship that respects the character of the building. We will not recommend full replacement if repair is the better option – and we will not cut corners on detailing to save time. Period homes deserve windows that look as though they were always there.
Book your free survey
If you are considering new timber sash windows for your London property, the most useful next step is a free, no-obligation survey. We will assess your existing windows, discuss what you want to achieve, and give you a clear, honest recommendation – whether that is full replacement or a different service better suited to your situation.
To take the next step, book a free, no-obligation survey, or get in touch with the team if you have any questions about the service.
