Replacement windows
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Replacement windows



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Windows are an important element in the character of old houses and buildings. They are literally the “eyes” of a house and can often reveal its history.

When the original windows of an historic building are removed or altered, it is deprived of some of its original character.

Most modern replacement windows do not match the profile, character, materials or historical value of the original windows and are generally unacceptable in historic buildings and conservation areas.

In historic buildings it is important to retain the original glazing pattern and materials.

The visual impact of uPVC replacement windows is totally out of keeping with the design and character of historic buildings and conservation areas and it is generally inappropriate to use them.

The most frequent criticisms of old windows are:

The timber is rotten. Older windows were built from better quality, slow seasoned timber than the softwood used in windows today. Often, serious rot is confined to the bottom rail or sill, which can usually be repaired by a good joiner.

They are draughty or rattle and jam. Opening and closing the windows can often be made easier by removing successive layers of paint and by fitting new sash cords. They can also be draft-proofed.

They need frequent repainting. It is still cheaper to repaint windows every five years than to replace traditional wood windows with uPVC or aluminium windows. Modern paints can extend the periods between maintenance.

Traditional windows



Before the 20th century, nearly all the windows designed were of two types. They were either casement or sash.

Casement (or side-hung) windows



These are windows with a hinged window-pane that swings in or out like a door. This style of window dates back to mediaeval times and is generally made of metal or wood.

Sizes of window-panes vary. To find out whether your window is genuinely old, or a modern replacement, check to see if the hinges are at the top of the window. If they are, the window is certainly modern. Older small-paned windows also have glazing bars (strips of wood or metal that separate the panes of glass in a window) that are slimmer and more elegant than those used today.

Traditional cottage windows were designed between 1600 and 1850. Normally, traditional cottage type casement windows were set well back into thick walls, built of cob or stone. Many windows of this period were roughly square. However, the number of panes does vary. In stone cottages that are not whitewashed or rendered, wooden lintels are sometimes exposed.

Replacement wood casement windows



Where wood casement windows are beyond repair, wooden replacement windows are usually the best alternative, provided they are a copy of the original.

However there are some problems:

Standard factory-made windows are cheaper than made-to-measure windows, but in most cases will not be the right size for the existing openings.

Both the design and detail of most modern standard sections are different from traditional windows and give a much coarser appearance. External storm-proofing, for example, is a modern addition that changes the character of the windows. “Stuck-on” glazing bars applied to the front of the window are also inappropriate.

Top hinged standard modern wood windows are inappropriate for an older house.

Another type of replacement window uses imitation “bulls eye” panes. These are not only out of place in older buildings, but actually dangerous, since they concentrate the sun’s rays to such an extent they can become a fire hazard.

Therefore, it is better not to use wooden windows with top hung vents, windows with imitation “bulls eye” panes, external storm-proofing or “stuck on” glazing bars.

Sash windows



When one or both parts of the window slides within the frame, this is known as a sash window.

In North Devon, many sash windows were built after 1850. These tend to have much larger panes of glass and wooden supports, called horns, on either side of the bottom of the top sash. Earlier Georgian examples of sash windows can be identified by the absence of these horns.

Other variations of sash windows include round headed windows and bays with curved sashes at each end.

Replacement sash windows



Most replacement windows are either uPVC, aluminium, aluminium covered with plastic coating or wood.

Manufacturers frequently claim that their uPVC windows are identical in appearance to timber windows. This is not the case for the following reasons:

The frame sections of uPVC windows are usually thicker and heavier in appearance.
The glazing bars are not glazing bars at all, but only flat strips of plastic between double-glazing, or strips stuck onto the front.
Traditional windows are more elegant.
The longevity of uPVC windows is still unknown and likely to vary. Some builders estimate that after 10 years they will crack, split, warp and disintegrate, with little possibility of repair.

Glazing



Until the 18th century, lead was used to fix smaller panes of glass within window frames because it was difficult to produce glass in large enough sheets to fill the entire frame. Today people buy windows where lead strips are stuck onto the surface of a continuous sheet of glass, and this never looks convincing since the original type of leaded pane window produced a varied pattern of light and reflection not reproduced by a single flat sheet of glass.

Conclusion



Whenever possible, replacement timber windows should be of identical design to the original windows. In the long run it is sensible to use high quality timber. There are occasions when it is best or appropriate to use unpainted timber, which can then be weatherproofed with high quality wood preservatives and this should last a long time.

The legal aspects



All listed buildings need permission to change the appearance of windows or even the material they are made from. Owners should speak to North Devon Council if they are in any doubt over whether their house is listed.

Listed Building Consent is required even if you are replacing inappropriate windows with the correct type of windows for that listed building.

In conservation areas where there are a large number of historic buildings (making the whole area of importance) we may issue directions under Article 4(2) of the Town and Country Planning Act 1990. This means you will need to apply for planning permission to carry out work that would otherwise have been permitted without consent. Householders will be informed if this happens.

It is a criminal offence to carry out unauthorised works to a listed building, including replacing windows. You are liable to be fined in a Magistrates Court and/or ordered to reinstate exact replicas of the original features.

In you are in any doubt, please always contact us.

Contact information



For planning enquiries, contact the Customer Service Centre:

Telephone: 01271 388288
For Typetalk: precede with 18001
Text: 07624 804042
Fax: 01271 388451
Email: customerservices@northdevon.gov.uk

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Our office hours are Monday to Friday 9.00 am to 5.00 pm.

Appointment based planning surgeries are held at:
To make an appointment visit one of the offices or phone 01271 388288.

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