Old, rundown windows could disrupt the aesthetics and energy efficiency of your home, but is it better to fix up the original units or install a whole new set?

Above: These replacement PVCu sashes from Roseview Windows feature strikingly slim sightlines that eco the heritage appeal of timber units

Windows are a vital part of every property’s character. They partner with the external cladding and roofing materials to set the tone for the rest of the property – and they have an important role to play in the interiors, too, both for style and thermal efficiency. So, if you’re tackling a renovation and your windows needs attention, it’s important to get the right result.

In most scenarios, repairing and replacing windows like-for-like is considered permitted development (PD). This means you don’t usually have to apply for specific planning consent, unless your project involves significant changes. Some councils are more flexible about this than others, so check whether you’re expected to precisely match the design, materials and method of opening of the originals before going ahead. Note that bay windows are likely to be classed as extensions that require formal permission.

Repairs are usually fine in listed buildings – but replacement tends to be a little more strictly controlled, and alterations to the style or the insertion of double glazing in such properties will require listed building consent.