What is a sash window?
Sash windows are the vertically-opening windows you often see on traditional buildings. Sash windows come in a variety of different builds and styles. The most common types of sash windows are Georgian, Victorian and Edwardian windows - each varying slightly different in style and number of windowpanes.
How much does a wooden sash window cost?
As our wooden sash windows are all bespoke products, you will naturally see a significant variation in cost. The price is dependent on how big or small the products are, how they're hung (whether they're on lead weights or springs), how difficult we expect the installation to be and what type of glass we need to use. We've compiled a list of what would usally be the average costs for these products, but please bear in mind that we will need to measure your products to get you an accurate costing. We provide site surveys as a completely free service - so there's no reason not to call us and get one of our friendly surveyors around! If what you're looking for isn't on this list, please don't hesitate to get in touch and ask us about it.
Ironmongery Options
Our traditional sash window furniture works well and looks great, with finish options like polished brass and satin chrome to match your space. But if you’re after something different—like a more traditional Fitch fastener, a Brighton fastener, or even a modern locking option—we can usually source and fit those too. Just let us know what you’re looking for.
Paint Options
Our sash windows are finished in your choice of colour from the RAL Classic range, giving you plenty of flexibility to match your windows to the style of your home. Whether you’re after a crisp white, a bold heritage tone, or something more modern, the RAL palette offers a wide variety of options. We use durable, high-quality microporous paint that’s designed to protect the timber while giving a smooth, long-lasting and breathable finish.
Timber Options
When it comes to timber choice, we don’t promote one type over another—each option meets our high standards for quality, finish, and durability. The main differences come down to cost and specific properties. Hardwood is around 30% more expensive than softwood and offers a slightly denser grain, while softwood provides a smooth, clean finish at a more affordable price. Accoya, on the other hand, is a specially modified timber designed for exceptional resistance to rot and movement, making it ideal for long-term performance in exposed conditions. Whatever the material, all our windows and doors are crafted to the same exacting standards.
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Previous Installations
We’ve installed wooden sash windows in all kinds of homes across London, from Georgian and Victorian properties to listed buildings. Every sash window is custom-made and expertly fitted to suit the character of the building. Below, you can explore a selection of videos showing previous installations that include wooden sash windows—so you can see the quality of our work for yourself.
Take a look at our reviews
We pride ourselves on our customer service. Take a look at what some of our previous customers say about us:
Historical Sash Windows
Sash windows have been a key architectural feature in British homes for centuries, evolving in style through the Georgian, Victorian, and Edwardian periods. Each era introduced its own distinct proportions, glazing patterns, and decorative details—from the elegance of Georgian six-over-six panes to the larger, bolder designs of the Victorian and Edwardian styles. This section looks at how sash windows changed over time, offering insight into the design history behind many of the traditional wooden sash windows still found across London today.
Georgian Sash Windows
Georgian sash windows are characterized by their simple, elegant design. They typically feature six-over-six, eight-over-eight panes of glass or nine-over-nine. One of the defining features of Georgian sash windows is their attention to symmetry, with each window having an equal number of panes on each sash.

Victorian Sash Windows
Advances in glass making by the Victorian period meant that consumers could opt for larger panes of glass. As these designs typically allow more light into the property and are easier to maintain, they proved extremely popular. Victorian sash windows often featured a single, central glazing bar, which gave the windows a cleaner and more streamlined appearance compared to the multiple glazing bars used in Georgian sash windows.

Edwardian Sash Windows
The Edwardian era saw a trend towards handmade, artistic designs and Gothic-style structures, which influenced the design of sash windows. With the growth of suburbs and larger houses without servants’ quarters, Edwardian sash windows featured larger panes of glass, simpler designs, and a single, central glazing bar for easier maintenance, reflecting the era’s emphasis on functionality and showcasing the homeowners’ wealth and ample living space.

Why you should upgrade your sash windows
The sash windows on many properties are usually over a century old. Often they are ill-fitting, draughty, difficult to use and very inefficient. Since the conception of sash windows, technology and quality have improved dramatically. You could be missing out on the benefits of modernised sash windows, casements and doors. Some of the main reasons you should look to upgrade your sash windows are:

Bolstered Security
Older sash windows are notoriously prone to security issues - a thief that knows what they're doing can gain access through an old sash window in no time. Modern sash windows come with additional security features and locking mechanisms as standard that outdated windows may not be equipped with.

Improved Aesthetic Appeal
Modern sash windows have both form and function. Timber sash windows also have a traditional feel that their plastic or aluminium counterparts can’t quite match - hence why they’re still popular.

Fully Customisable
Sash windows allow you to style your windows exactly how you want them. Choosing between the number, type and arrangement of windowpanes, hardwood or softwood timber, and double or acoustic glazing means there’s an option for everyone - especially if you’re looking for a change.

Easy To Maintain
Our products and paints are extremely durable. Under normal circumstances you will not need to paint your sash windows within ten years. It's good practice to check on windows that are more exposed to the elements more regularly.

Increase the value of your home
Any estate agent will tell you that sash windows improve the curb appeal of your propety, adding value and making your home more attractive to buyers.

Increased Energy Efficiency
If your home still has it's original sash windows, they're likely to be single-glazed. Higher-quality, thicker timber allows modern sash windows to have double glazing - helping to heat up your home and save you money.
Insurance backed guarantee & FENSA certificate
At Core Sash Windows, all of our windows come with a 10-year guarantee and are FENSA certified. This means the fitter has installed anything from our product range in accordance with strict health, safety and quality standards - meaning you’re getting the best results.
Frequently Asked Questions
Provided you own the home, you do not need planning permission to change, replace or upgrade your sash windows, casements or doors. If you live in rented accommodation, you’ll need permission from the landowner before undertaking renovations.
Outdated sash windows are subject to wear and tear. If they’re not maintained properly, moisture can cause the timber in the frames to rot and weaken. This can cause the wood to warp and buckle - causing drafts and noisy rattling. Some of the signs your sash windows might need an upgrade are: Peeling paint Water Ingress Stiffness on operation Rattling on operation Self-raising or self-lowering Draughts or howling Rotten timber Bending, bowing or breaking of the timber However, with proper maintenance, sash windows can remain in tip-top condition for decades with the right fitter and quality materials. If you’ve noticed these symptoms on your windows, it might be time for an upgrade. Get an instant quote or contact us today to find out how we can help you fit your dream windows.
Modern sash windows are incredibly safe. While contemporary sash windows may have been more susceptible to break-ins in the past, stronger double glazing, more durable timbers and security features - like sash window screw locks and fasteners - mean security issues are no longer a concern.
Yes, you can. Modern sash structures can support thicker, more durable timber, offering more room for double glazing and improved insulation - should you upgrade.
Measuring your sash windows may seem complicated, but it can be done in three easy steps. Extend the measuring tape down the entire vertical length of the sash box and record the measurement. Extend the measuring tape across the horizontal width and record the result. Send the measurements off to us - we’ll handle the rest. It’s crucial to remember that these measurements are only accurate for sash replacements. If you need the sash box changed as well, add 135mm to the vertical length and 150mm to the width to cover the measurements for the additional box unit. If you need additional assistance or are just unsure, we’ll conduct a no-obligation survey - free of charge - to give you peace of mind knowing everything’s being handled correctly.
Yes, it is possible to soundproof sash windows. While additional glazing reduces the sound naturally, discreet acoustic glass can be fitted for soundproofing. Looking for new sash windows? Core Sash Windows boast an extensive range of fully-customisable windows, casements and doors to fit all specifications. Book your free measuring and evaluation by getting an instant quote and transform your home today.