Maintain old windows to ensure efficiency for years to come

Window shutters can transform traditional windows from draughty to energy-efficient, claims the chief executive of English Heritage.

Dr Simon Thurley, writing for FT.com, emphasised that older windows can prove efficient for years if adequately maintained. In that regard, he said the owners of period properties do not need to replace original windows with PVCu equivalents in order to meet energy targets.

Almost a third of Britain’s carbon emissions originate as a result of heating the home and Dr Thurley believes that a significant way to cut emissions is to make energy efficiency improvements in existing buildings. Himself the owner of a listed property, Dr Thurley pointed out that windows have become “the villain of the piece” in terms of home energy loss.

This is an issue that is increasingly attracting the public’s attention, least of all due to increased bills. In Bath, a city filled with period buildings, a recent thermal imaging initiative highlighted just how eco-friendly – or not – locals homes were. Hundreds of households took part, according to This Is Bath, discovering how much energy was escaping from their windows.

The doctor believes the installation of new windows has damaged the appearance and significance of older houses. Statistics show that 40 per cent of homes constructed between 1850 – 1899 now feature double glazing.

Research suggests that maintained traditional windows can perform as well as those made from PVCu though. Dr Thurley agreed, asserting that fitted window shutters can help achieve U value (heat loss per square metre of a building) targets of lower than two.

“My well-maintained windows of 1860, which have tight fitting shutters, have a U value of around 1.7 on a dark night,” Dr Thurley said, citing secondary glazing and thick curtains as other effective measures.

“The fact is that properly maintained traditional windows can be efficient and effective for hundreds of years”.