Double Glazed Sash Windows

Double Glazed Sash Windows

If you are considering new sash windows for your home, then timber sash windows are an incredibly popular choice with many homeowners, particularly those in London.

New windows in London


Why opt for timber sash windows that are double glazed?

You might be contemplating replacing the existing sash windows in your property because they are no longer offering you a good level of energy efficiency or because they are simply not in keeping with the style of your property. If you live in a conservation area you may be limited on the type of window replacement that you make and our timber sash windows, which offer a traditional look with all the benefits of double glazing are the ideal choice.

Double glazed sash windows islington

At Core Sash Windows we specialise in the supply and fitting of timber sash windows and casement windows. All of our fitters have years of experience working exclusively fitting these types of casement and sash window. They know our product range inside out and know all of the common issues that may occur during a sash window fitting, they are experts when it comes to ensuring your new sash windows fit properly and there are no draughts. This means that they are able to quickly resolve any issues and provide a very positive user experience to all of our customers.

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What are double glazed sash windows?

If you’re unsure of what these types of windows are, let us explain further. A double glazed sash window is a sash window that has double glazing panes installed in it.

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A sash window is one that is typically made of one or several moveable panels. The sash is the moveable part of the window, which is made up of the horizontal and vertical frames that hold the glass within. On double hung windows, there is a check rail, which is where the upper portion of the lower sash and the bottom portion of the upper sash make contact.

Double glazed sash windows detail

Double glazing is a very popular option with many homeowners. It is ideal for reducing noise pollution for those homes that are located near to busy roads, and it is also a great guard against heat loss in the home. With energy efficiency becoming increasingly important with homeowners due to rising utilities costs, installing double glazing is a good way of making the home a more energy efficient environment, and also reducing those monthly outgoings.

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How are double glazed windows constructed?

Now we’ve explained what a sash window is, let us look at double glazing and why it could be a popular choice for the modern homeowner.

Double glazing panes are made up of two sheets of glass with an air gap in between. This gap is usually filled with an inert gas such as krypton. Effectively, a double glazed window is a sandwich comprising two pieces of toughened glass, each piece will measure around 4mm in thickness with a larger gap in the middle.

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How big is the gap and does it matter?

The air gap of these glazed windows can be anywhere between 6mm to 20mm – the bigger the gap the better the performance of your windows when it comes to combatting all of those unwanted loud external noises. The whole unit is sealed together and then placed inside the window frame to create your timber sash windows.

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Can you replace the glass unit rather than fitting a new window?

If you already have sash windows but are experiencing issues with them misting up between the panes of glass then you may think that your only option is to have the entire sash window replaced; this is not the case. In addition to the fitting service that we offer we can also repair existing windows and in the case of a window that is misting up it can be as simple as having just the glass unit of your window sash replaced rather than the entire sash window. This can be much more cost effective, and of course less disruptive.

Are double glazed sash windows a good investment?

Timber windows are a beautiful feature in any older property; however, you will usually find that this type of original sash window is only single glazed. This means that it will only have a single pane of glass in the frame, and this is not that great when it comes to keeping out external noise or cold. Whilst the noise may not be an issue for many people the cold certainly can be. If your sash windows are not keeping out the cold it may mean it is necessary to have the heating on higher and for longer; and this can prove to be incredibly costly in the long run due to the increase in your heating bills.

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Energy efficiency

Double glazed, or even triple glazed panes, are much more energy efficient. You may choose to replace your entire sash window with a new timber sash and double glazed unit, or simply have double glazing added to your current timber windows so that they remain in keeping with the overall character of your property. The choice is yours. We would be happy to talk to you about your options and provide guidance on what we believe could be the better choice for your property.

Many older properties, particularly in places like London are located in conservation areas. These areas are often governed by particular regulations regarding the type of sash window replacement work that can be carried out on a property and require that any alterations are carried out to strict guidelines. It can be a good idea to check for this information before you begin your search for new windows so that you can find the right company in London, or nearby who can offer you the right services. Our timber framed double glazed sash windows are the ideal solution to this problem and retain many of the features that can be found in original sash windows unlike the alternative of UPVC windows.

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How much does it cost to install double glazed sash windows?

Every home is different and so when it comes to windows it is not always that easy to give customers an exact price without visiting the property in order to gain all of the relevant information to complete a full quote. However, you can get an idea of price by using our instant quick quote feature.

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The number of sash windows that you are looking to replace, and whether they are the original sash windows, the size and type of sash windows that you would like – these will all have a bearing on the cost. If you would like to know exactly what it would cost then please do not hesitate to give us a call to arrange an appointment. One of our sash window experts will be delighted to visit you and collect the information that we need in order to do this. We will measure your current sash windows and then discuss your options for replacement sash windows with you. It may be that you will only need new double glazed sashes in your current window frames, and we can certainly assist you with any queries you may have about replacement glazing. If we feel that your home would benefit from a full box frame replacement we will advise you on what work might need to be undertaken and quote on this basis.

Measuring sash windows

We offer wide range of different styles of windows with a range of features, we will be more than happy to discuss these with you in order to give you the most accurate costing for your windows. Your choice of sash window furniture, the colour options available, the number of glazing bars and of course if you would like traditional features such as sash horns will all have an effect on the cost.

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Do you fit UPVC sash windows?

As a company we only supply and install timber windows, we have made the decision not to work with UPVC sash windows as we believe that the look and aesthetic that a timber sash can add to the character of buildings simply cannot be beaten, we also know that this is an important consideration for many of our London based clients. We only use the best quality wood for all of the casement or sliding sash windows and all of our frame work, sashes and even the glazing bar work is done using durable European Redwood. This is a wood that gives great performance and will help your sliding sash windows to last for many years.

If you’re wondering whether wooden sash windows would work for your home and are looking to replace UPVC that is already there, we’d be happy to help you. Just get in touch with our team and we’ll let you know what options might work best for your property.

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What glazing options are there for sash windows?

Traditionally sash windows would have been single glazed and during the Georgian era it would not have been uncommon for each sash window to have had a number of glazing bars. A glazing bar is the pieces of wood that were used to separate the glass in the window pane and allowed for smaller panes of glass to be used to make up a window rather than larger pieces of glass were harder to come by. Sometimes referred to as Georgian windows these sash windows can often be found as a feature of some new build housing developments where they are very in keeping with the type of home that is being built.

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Double glazed sash windows – a great choice

Double glazing is an excellent option that can easily be added to your timber sash windows, if you currently have single glazed units in place and the frames of your sash windows are still in very good condition then it may simply be a case of replacing the current glazed unit with new double glazed ones. This will allow you to keep the original sash windows and the aesthetic of your home intact.

For ultimate energy ratings, and particularly if you live in a very noisy area you may even want to consider having all of your sash windows replaced with triple glazing. This will help to keep your home noise free without taking away any of the charm.

Double glazed sash windows islington apartments

Is double glazing more energy efficient for windows?

When it comes to the glass in your windows there are a range of different options that you may wish to consider, however it is widely accepted that double glazing offers a much better level of energy efficiency over single glazing. The clever construction of the double glazed units that are put into your window frames offers a much thicker barrier between the interior of your home and the weather outside. This helps you to keep your home more insulated and make it warmer and ultimately this should mean that you will be able to keep your heating a little lower and therefore reduce your heating bills. With electricity prices continually on the increase this is certainly helpful

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With the addition of a good draught proofing system to your sash window you will be able to prevent those annoying draughts that can make the house incredibly cold and often have people reaching for the heating dial. This will certainly help to make your home more energy efficient, particularly when combined with double glazed units on your windows.

For improved energy ratings, and particularly if you live in a very noisy area, then you may even want to consider having all of your sash windows replaced with triple glazing, this will offer you a better performance from your sliding sash windows and will help you to keep your home noise free without taking away any of the charm.

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Where can I see examples of your windows?

Over the years we have fitted windows for many homeowners who have been delighted with the result of the work we have undertaken. If you would like to see examples of some of the work that we have completed there are a selection of previous installations on our website, these showcase not only the styles of sash windows that we can offer but also what a difference the right timber windows could make to your property.

If you would like to learn more or would just like information that the products we have to offer then please get in touch. You can reach us via e-mail, by telephone, or can request an instant quote by simply clicking the button below. We look forward to helping you get the windows that would suit your property best.

Double Glazed Sash Windows Company


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call us: 020 3302 2060 or email: [email protected]

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