Sash Windows

Sash Windows originated in 17th Century England. They quickly became a large part of our architectural heritage with their distinctive aesthetics and design typically featuring in buildings of the Georgian, Edwardian and Victorian eras. But much like many architectural features, different designs and styles and designs of windows have dropped in and out of fashion over the years, and Sash Windows being a good example of this. In fact, it’s very rare to see modern homes constructed with Sash Windows as standard. However, in recent years Sash Windows are once again finding favour with home owners, particularly as part of the wider trend of going back to old fashioned aesthetics and traditional features except in more durable and efficient modern materials. So, let’s take a closer look at Sash Windows.

What are Sash Windows? 

Sash Windows are constructed of one or more movable panels that are referred to as ‘sashes’ and are held together by glazing bars. The individual sashes are traditionally paned windows, the number of panes depending on the era. However, in modern times Sash Windows are now seen to contain one individual sheet of glass (or sheets, in the case of double glazing).  

The history of Sash windows

Sliding Sash Windows were originally designed to overcome the issue of narrow streets in 17th Century England where opening of windows outwards would have caused an obstruction to passers-by through windows for opposite buildings touching each other so forming a barrier and also block light.


They rose to the fore of architectural design after the Great Fire of London in 1666 in the period commonly referred to as ‘English Baroque’. During this era, many iconic buildings such as Kensington Palace, Ham Hall, Greenwich and the remodelled Hampton Court incorporated Sliding Sash Windows in their design.


The classic arrangement of three panes across by two up on each of two sash, giving a six over six panel window is often found in Georgian and Victorian houses, and many late Victorian and Edwardian suburban houses were built using standard sash window units of approximately 4 feet in width.


There were several developments and style changes in Sash Windows over the years therefore, if you own an historic period property replacement Sash windows must be carefully selected to ensure that the right period is chosen. 

Historic Image of Casement Windows in England 1898

How does a Sash window work?

Sash windows don’t open on a hinge. A traditional ‘sliding sash’ window is usually made up of two sashes that slide up and down (or side to side), one in front and one behind, in vertical grooves that are counterbalanced by lead weights on cords, or more recently, spiral balances, which allow the window to be opened. 


A Sliding Sash window can be opened at the top or bottom. Or if you have a double hung window by sliding the top sash downwards – this design of Sash window is excellent for ventilation by promoting airflow through the property. Traditionally Sash windows have no outward swing, although more modern Sash windows have been designed to tilt in and out for ease of cleaning. When the Sash window is closed the top and bottom sash lock together at the midrail which prevents the window sliding for added safety and security. 


Some designs of Sash windows have handles attached that can be used to open and close them.

What glazing (glass) is available in Sash Windows? 

Generally modern Sash Widows will contain double glazing, but it may also be possible to choose from other glazing options such as safety or acoustic glass according to the nature of your property. Other factors which could influence the type of glass that can be used within a Sash


Window include:

The space within the Sash – glazing will of course need to fit into the sash therefore if, for example, acoustic glass was being installed this could only be done if a complete replacement of the window has been commissioned. It may be necessary to replace old Sash Windows if they cannot be double glazed.

Listed building status - fitting double glazed windows into a listed building can be very challenging as the right permission will need to have been gained before work can commence. It may necessary to stick with single glazed windows that are as thermally efficient as possible by restoring the sashes or to include very thin double glazing.

Budget – installing specialist glazing such as acoustic or safety glass will of course add to the cost of your windows. We recommend discussing your requirements in order that we can provide you with a quote for different types of glass in your new Sash Windows to see it if it will be affordable according to your budget.

What are the benefits of Sash Windows?

Comfort: When used in conjunction with double glazed windows, Sash Windows have been proved to reduce up to 40 decibels of noise. This reduction in noise and disturbance will provide you with a calmer and quieter environment to live or work within. 


Sash Windows are also know to provide excellent insulation properties as the sealed element locks the heat into a room allowing less air to pass through, so retaining heat and providing you with a warm and cosy environment. During the warmer summer months, Sash Windows offer a fantastic means of ventilation allowing entire rooms to be easily ventilated. 

Easy to maintain: Sash Windows are widely acknowledged as being easy to maintain due to the features of the sashes tilting either upward or being able to be lowered to facilitate easy and thorough cleaning which of course helps to keep Sash Windows looking like new for longer.

Security and durability: Locks can be installed on Sash windows that will allow the windows to be secure and safe whilst also able to be opened for ventilation. And to further enhance security; double glazed Sash Windows are available which are highly durable and hard to break.  However, for maximum security, triple glazed Sash Windows offer the benefits of extreme strength and durability.


Money saving: Although this is very dependent upon the property or/and the area that you live in, Sash Windows can also help to save money. For instance, uPVC is the best alternative to timber for cost efficiency as wood costs an estimated 40% more than uPVC does for Sash Windows.

A touch of style: As technology has improved manufacturers abilities to manipulate materials, the design of Sash Windows have become more and more aesthetically pleasing. Sash Windows are able to be easily customised to match your style, personality or property theme whilst also remaining cost-efficient. They provide a very sophisticated look that combines traditional with modern.

What are the disadvantages of Sash Windows?

Sash Windows have the reputation of being relatively high maintenance, but the advantages that they offer in terms of aesthetics, style etc. far outweighs this disadvantage. The traditional solid wooden sash windows do suffer from such issues as rot, swelling and/or distortion of the woodwork, and rattling in high winds due to wood shrinkage. However, these problems can be solved by regular maintenance and expert repair and the introduction of draught stripping. 

Another issue that needs to be watched out for is the common problem of painting the sash stuck. Additionally, the sliding mechanism makes Sash Windows more vulnerable to these problems than traditional casement windows. Having said all this, well-maintained sash windows should stand the test of time without needing replacement parts replaced. It is also possible to clean all the glass from within the building by sliding the two panes to different positions.

How do you I ensure that my Sash Windows keep working as they should?

As with all things, Sash Windows require regular and careful maintenance in order to keep them working they should be. If your property has older Sash Windows they may require more maintenance to keep them in good condition whilst newer sashes will need some degree of maintenance such as regular cleaning and the occasional lick of paint. 


Much of the appeal of Sash Windows is in their appearance, so it’s important to keep them looking their very best. If course should your Sash Windows need more expert maintenance repair or even replacement, the team here at Welbeck Windows are happy to assist, just give us a call on 0203 583 3525 for our expert advice.


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