Double glazing is often hyped in the drive to save energy but older-style windows, brought up to their maximum efficiency, can be just as effective in keeping draughts at bay.

Simon Tuke and Anthony Williams, of Oxford-based Tuke-Williams have, over the years, applied their craftsmanship to restoring countless sash windows.

Mr Tuke points out that these also offer the benefit of being easily opened so a breath of fresh air can continue to be welcomed in rather than being permanently sealed out.

“Repairing windows is often a much cheaper alternative to replacement and a much greener approach to house maintenance,” he added.

The two craftsmen, both in their late 40s, have been working together on various projects for many years, for various clients. Seven years ago they set up their own companies, Board Stiff for the bespoke furniture and general carpentry services they offer and Dr Sash for their more specialist work on sash windows.

“Between us we have 50 years of woodworking experience,” said Mr Tuke.

For the more recent amalgamation of their two lines of business they are using just their own names and trading as Tuke-Williams.

The window work is more seasonal, with less call for it during the summer months but leaving any problems until the autumn is not to the client’s advantage, they both point out.

“If any work needed is not done in the summer months, by the time you get to the autumn and winter the paintwork will not dry out so quickly,” said Mr Williams.

New wood needed in the frames will also dry out more quickly when it is warm and the temporary open space while a window is removed for repairs will not be letting in wintry weather.

Older-type sash windows are well-worth any time and money spent on them.

“One hundred-year-old windows can go on indefinitely, provided they are maintained well and treated carefully,” said Mr Tuke. “Once repaired they can be enjoyed by many generations to come — and that is not something you can expect with UPVC replacement windows.

“Neglect is the cause of most problems, where householders have let their windows deteriorate for too long. The wood of the frames flakes and water gets in.

“And where people have attempted their own do-it-yourself repairs of a broken sash cord they can have upset the delicate balance of the pulley system with its lead weights, which is an important part of their operation.

“Broken sash-cords are the most common problem we come across, sometimes having led to windows becoming permanently closed and eventually with the frames painted over and sealed shut. But they are a simple problem to resolve for somebody who knows what they are doing.” Mr Tuke said.

“The first thing people who call us in want is to be able to get the window open again.

“We can do whatever is needed — repainting, replacing the glass, right up to a full refurbishment.

“Where glass is concerned however, we try to keep the original. The ultra-flat modern replacement glass gives a different effect from older glass, where there is a slight ripple that can just be seen in it. If retention is not possible, we use the highest quality glass to replace it.”

Sash cords nowadays come in stronger and much longer-lasting materials. They may be made of cotton, nylon or a combination of the two. There has been subtle upgrading over the years,” Mr Tuke explained.

Draught proofing can provide a further improvement to existing widows — bringing the added benefit of noise reduction.

Once back in working order, repainted and weatherproof, the widows are fully ready to withstand the worst that winter wind and rain can bring.

“Some of the windows we worked on five years ago still look just as good as when we finished them,” Mr Tuke said.

Sash windows could be regarded as something of a niche market and are very much a feature of Georgian, Victorian and Edwardian buildings, in keeping with the styles of the period and are also used in more modern architectural design.

But there is strong demand for their services with work from as far away as Shropshire.

“We have worked on some lovely houses in London,” said Mr Tuke. “Cheltenham has lots of houses with sash windows and if you look around Oxford you will find there is a high percentage here.”

The earliest are likely to date from the late 17th century. Mr Tuke explains the word ‘window’ is derived from an original ‘wind door’.

The additional furniture making and other wood-related business was brought in to generate work during the quieter summer months.

Commissions include bookcases, audio-visual units, tables and wardrobes.

Designs are discussed with clients and finalised according to their wishes and the work carried out either in situ for fitted fixtures or in their own workshop in Summertown.

“The two streams of work run well together in parallel,” said Mr Tuke.