Repair or replace

Repair or replace?

There is often an assumption that old windows will need to be replaced if they are

in need of repair and because of this many original windows are lost - and money

spent – unnecessarily. An historic building’s character depends upon correct

proportions, material and detailing as well as the retention of historic fabric. Careful

repair ensures that these features can be retained.

A window often can appear to be in worse condition than it actually is, so make

sure that the assessment is properly carried out, as detailed below. A specialist

joiner, or blacksmith/metal window restorer for metal windows, will generally be able

to advise on whether repair is possible, but bear in mind that some companies will

prefer to make a new window than undertake time-consuming repairs.

Original windows should only be replaced as a last resort

Historic joinery is usually made from naturally seasoned hard and softwoods, and

if the timber is properly maintained, it is likely to outlast a modern replacement

window. Historically timber was slow grown and naturally-seasoned, unlike the

majority of modern timbers, and producers did not rely upon preservatives and

stove-drying.

It is very uncommon for metal windows to be beyond repair. Although they may

appear to have corroded, surface rust looks much worse than it is. Metal windows

are often capable of restoration either in-situ or can be taken away to a workshop

for more extensive repairs.

Modern windows tend to be poorly detailed and heavy in appearance with the

‘storm-proofed’ opening ‘lights’ set outside the main frame, protruding cills and

no or crudely detailed mouldings. Double-glazing windows are easy to spot due

to their external mirror-like reflection and spacer bars. Modern materials such as

uPVC, stained hardwoods, ‘stick-on’ lead or glazing bars only add further to the

loss of character of a period building. The difference between traditionally detailed

timber casement and sash windows, and modern uPVC alternatives, can be seen in

the images on this page.

Unlike traditional timber windows a modern uPVC window is not easily repaired and

often has to be totally replaced when it fails. The repair of a timber window will use

far less resources than the manufacture of a new window, and is, therefore, also far

more sustainable.

The starting point for any repair or alteration work to an historic building is to seek

professional advice. It is also very important to record and photograph original

windows before they are altered or removed. Where windows with leaded lights are

being removed for repair, it may be prudent to make a rubbing of the leaded lights

in order to record their arrangement.

The installation of a new window in a listed building will require listed building

consent.