Sash Windows: Design Advice

ABOVE: Early Georgian windows often had many small panes, as shown in this eight-over-eight design.

Good Design vs Bad

One of the main questions that people need answers to is whether opting for double glazing will compromise the authentic appearance of sash windows. Of course, sash windows would not originally have been fitted with double glazing and it is the opinion of many experts that if windows are properly fitted and draught-proofed there should be no need for it. The 20mm width of a typical glazing bar is too narrow to hide the spacing bar of a double-glazed sealed unit, meaning that heavier glazing bars have in the past been used. One solution is to use dummy timber glazing bars, bonded to either side of a double-glazed unit, but not running through it. And it is also now possible to find double-glazed windows with smaller spacer bars and glazing bars which have been whittled down to around 25mm. Take a look at those from The Original Box Sash Window Co. (0800 169 3198; boxsash.com). In addition, there is a new energy-saving glass by Pilkington called energiKare (pilkington.com), which consists of two panes of glass separated by a vacuum gap of just 0.2mm, aimed directly at the sash window market.

Mock sash casement windows are a cheaper option than sliding sash windows and can be bought off the shelf in standard sizes — it is even possible to fit them on a DIY basis. The top sash is hinged and opens like a casement window. They also come complete with trickle vents. However, despite the benefits they never truly replicate the look of authentic sashes.

ABOVE (clockwise from top left): PVCu sash windows from The Bygone Collection (0800 591 854; bygonecollection.co.uk); Three designs from Mumford & Wood, (01621 818155; mumfordwood.com).

Need to Know...

Where to buy

Your local builders’ merchant will stock a good range of standard windows, often at competitive prices. Local joinery firms are also a good choice, with many specialising in sash window manufacture. Lead times can, however, be longer than with sash window specialists, due to small teams. Finally, sash window specialists usually have an indepth knowledge of styles and individual requirements. Get several quotes and take note of lead times — they can be several months, so windows should be planned well in advance.

Who will fit them?

If you buy off the shelf or from a local joiner, the chances are that you will have to find someone to fit the windows. Your carpenter or joiner may have the skills to do this. If ordering from a specialist, they usually offer a supply-and-fit service.

Further reading:

• All About Sash Windows
• Sash Windows Explained
• How to Restore Sash Windows