We manufacture and install replacement timber casement windows across London and the South, providing a supply only service nationwide

All our replacement timber casement windows are individually manufactured in our workshops in Berkshire. There are many different design configurations of wooden casement windows that we are proud to be able to replicate depending on your bespoke requirements. We also have a Classic Range which was developed over many years and covers most period design requirements.

Our timber casement window styles include:

Flush casement windows | Storm proof casement windows | Traditional casement windows

Timber flush casement windows are a more traditional design style of casement window than storm proof casement windows. Flush casement windows sit flush within the frame, creating a flat surface on the outside. In contrast, storm proof casement windows (sometimes referred to as lipped casement windows) overlap the window frame when closed.

We are also able to replace casement sashes (the moving parts of the timber casement window) if the frames are still in a good condition.

Timber Casement Windows in Period Properties

At The Sash Window Workshop all our replacement timber windows are designed to add charm and character and be in keeping with your home, while providing modern benefits such as double glazing.  We can manufacture casement windows to suit a range of period properties and listed buildings, including Edwardian, Victorian and Georgian properties.

If your windows are in a good condition we can repair the existing window by carrying out our draught proof and overhaul service.

We also offer a range of other replacement products, including wooden sash windows and external timber doors such as French doors, front doors and sliding and bi-fold doors.

Where We Install Casement Windows

We have extensive experience installing timber windows in period properties across London, Berkshire, Hampshire, Surrey, Oxfordshire, Hertfordshire, Buckinghamshire, Wiltshire, Essex, Kent, West Sussex, East Sussex and Bedfordshire.

We also offer a supply only service for new timber casement windows across the UK.

Made in Britain

We are proud to manufacture all our wooden casement windows from our workshop in Berkshire. Using the latest technology alongside the skill of our expert craftsmen, all our new windows are bespoke, manufactured to meet our customer’s design requirements.

Our casement windows come fully factory finished.  We offer a wide range of glazing, ironmongery and paint / stain finish options to suit your requirements.

High Quality Materials

The materials that we use are of the highest quality. Our years of experience and knowledge ensure that we use only the best and most durable products, providing you with a high quality performance window. We are FENSA registered, FSC® Certified and our new casement windows come with a comprehensive guarantee.

The majority of our replacement casement windows are manufactured in AccoyaTM, a durable, sustainably sourced modified wood which comes with a 50 year anti-rot guarantee.

Unsure what type of windows you have? Sash windows slide up and/or down to open, whereas casement windows open on hinges, like a door.
To view examples of our previous work, view our gallery pages.

New casement windows are glazed in accordance with Building Regulations and the relevant BS standards (EN 1279) to offer the best in energy efficiency. We work with a variety of different glass types to suit your specific needs. As standard, most of our new wooden windows are double glazed.  However, we can manufacture single glazed windows to meet listed building requirements if required.

We also understand the importance of providing ironmongery that is not only elegant, but also secure, providing a high level of security for your home.



Accoya Anti-Rot




Double Glazing




Draught Proof
*Joinery guarantee will depend upon the timber chosen