Georgian bars, astragal bars or keep original glazing bars?

Georgian bars, astragal bars or keep original glazing bars?

Astragal and Georgian bars in modern window replacement

Astragal bars are a hotly debated design feature for modern window replacements as they help to recreate the traditional style.

This is particularly important when you change windows in period properties and do not want to spoil the traditional look of your house. 

Keep original windows and change glazing

But how about an idea of keeping original glazing bars and windows and just replacing single glazing with thin profile vacuum double glazing.

Change single glazing

This way you can keep original timber windows, keep the traditional look of the property and get all the benefits of triple glazing. Yes, vacuum glazing has similar thermal properties to triple glazing.

Let’s first of all look at at what is the difference between astragal bars, Georgian bards and original Georgian glazing bars. 

What is an Astragal bars?

Astragal bars are a modern imitation of glazing bars on period sash windows. Glazing bars on period windows were used to hold the glazing inside the window frame. The reason that original glazing bars were used on traditional sash windows was that, at the time, glass manufacturing was a difficult and challenging process. This meant that glassmakers couldn’t produce large panes of glass. So, glazing bars were designed to hold the panes of glass into the wooden frame, allowing the windows to be much larger, and providing the now iconic look of sash windows.

Astragal bars are a modern replica of glazing bars fitted to the inside and outside of double glazing units. Instead of holding individual pieces of glass in the frame, they are used to divide a single pane of glass into sections. This provides the classic and iconic look of a sash window from a period home but makes manufacturing and installation easier.

Why astragal bars used in modern double-glazed windows?

Today, of course, astragal bars are used on modern windows as design features to give modern homes a traditional appearance. This brilliant piece of window technology has become a statement piece nowadays. However, most modern astragal bars are now stuck onto a single large pane of glass to give the effect of many panes of glass.

astragal bars used in modern double-glazed windows

How do original glazing bars in period windows work?

Glazing bars are an integral part of the woodwork for a traditional sash window. Think about the wooden frame of a casement window like a photo frame; the photo would go where the pane of glass (glass unit) normally would. However, if you had lots of smaller photos to display (or lots of panes of glass to install, like in a sash window), you’ll need lots of smaller frames within the larger frame to display the photos.

original glazing bars
georgian sash glazing bars

So, glazing bars are essentially slimmed-down parts of the wooden window frame.  The astragal bars hold the individual pieces of glass in place within the wooden frame and offer protection from air loss and water from entering the property.

Beading or putty is then used to hold the panes in place within the glazing bars.

What is the difference between astragal, Georgian bars and original glazing bars? 

The difference between astragal and Georgian bars is that astragal bars are fitted on both sides of a double glazing unit, whereas Georgian bars are fitted to the internal side of the double glazing unit only. 

Astragal bars
Astragal bars
Georgian bars modern sash window
Georgian bars

Astragal and Georgian bars are different to the original glazing bars in by function, traditional gazing bars in sash or casement windows, were designed to hold individual panes of glass and make the structure stronger while astragal and Georgian bars mostly play decorating, and visual roles.

How many panes of glass are in a Georgian window? 

If we are talking about original Georgian windows,  the number of glass panes depends on the glazing configuration and type of the window. In classic 6 over 6 sash windows, there are 12 individual panes of glass. In 3 over 6 configurations the same logic applies, all glass panes separated by a glazing bar are individual pieces of glass.

Wit modern sash windows, the situation is different, usually, each moving sash has just one double-glazed unit of glass and only Astragal bars make the window look like it consists of many glass panes. 

8 over 8 Georgian sash
8 0ver 8, 16 panes of glass per window
10-over-15
10 over 15, 25 panes of glass per window
6 over 6
Classic 6 over 6, 12 panes of glass per window

Our double glazing retrofitting method saves original Georgian glazing bars 

We keep original glazing bars from inside and replicate the exterior bars with timber and putty identically to the original.

We do this to preserve the look of the window and save as much of the original joinery as possible. So the style of your window will look the same as it always has. It still has the original Georgian glazing bars, but it will have modern double glazing to protect you from your home temperature changes. 

original georgian glazing bars from inside
original georgian glazing bars preserved

One double glazed unit per one sash for better insulation 

The photo above shows a beautiful, original Georgian sliding sash window. Here we have retrofit double glazing into both sashes of the sash window. 

We install only one double-glazed unit per sash because it offers better thermal insulation. 

one double glazing per sash
installation of double-glazed unit per sash
Orignal window with vacuum glazing

Change the style of your windows by adding or removing glazing bars 

You can add Georgian bars to windows as design features, and many modern window manufacturers do this as it is a very popular look. If your property is listed, you likely won’t be able to make such big changes to the windows without planning permission.

If your property isn’t listed, though, adding these bars can make a really big impact on the style of your property.

Adding glazing bars, changing the look of your windows, and thus, the look of your home. It can be a great way of adding a new character to an old property. With our window restoration experience, we can help you achieve this. 

The below photo shows how our team changed the change centre bar sash window style to half Georgian while replacing single glazing with double glazing and renovating frames.

change sash window design of original windows

Can you add Georgian bars to the windows?

Yes, we can add Georgian glazing bars to your existing windows to change the style of your existing windows by matching the profile of your sashes.

The photo below shows bay windows’ new glazing bars. All new glazing bars’ joinery fits well with old sashes. After painting, you will not recognise that those glazing bars are not original. 

new half georgian bars from inside

New Glazing bars match the existing window profiles

We take a lot of pride in our sash window restoration services to ensure that our work looks exactly the same as the original work. Our aim is that anything we add to your windows doesn’t distract from the beauty that is already there.

When we fit new double-glazed units into original frames we make you the original windows will look the same after double glazing. If we will need to produce new parts of the window due to rot or the requirement to add new glazing bars, we will always match profiles that are already there. 

new georgian bars match existing profiles of the window

If you are currently looking for new double-glazed windows to replace your original sash windows consider our retrofit service first

By renovating and fitting new double glazing instead of single glazing in your existing windows, you can keep the classic and iconic windows that really make your home come alive but get all the benefits of double glazing.

We use modern window technology to ensure that your current windows can match the energy efficiency of any modern double-glazed window without taking away any of the charms from your property at all.

Chameleon has years of experience offering our window restoration service to people that want to keep their wooden windows but bring them into the 21st century with brand new double glazing technology. 

Our sash window double glazing projects

    Fitting double glazing to existing windows in Chelmsford

    Fitting double glazing to existing windows in Chelmsford

    Double glazing retrofitting in Wing

    Double glazing retrofitting in Wing

    Double glazing of original sash windows

    Double glazing of original sash windows

    Double glazing Georgian sash windows with FINEO glass

    Double glazing Georgian sash windows with FINEO glass