How to Restore Timber Sash Windows in Cambridge

Many homes in Cambridge have sash windows that are traditional and homeowners are proud of their appearance. However, sash windows can get stuck and be difficult to open or close. This is usually due moisture, which can cause the wood to expand.

Traditionally, window boxes utilized chains, cotton cords or lead weights to operate. Modern sash windows come with hidden springs to overcome this issue.

1. Aesthetics

Unlike PVC-u windows that are manufactured to modular imperial sizes the timber sash windows are able to be restored to their original dimensions. This permits the re-installation of timber sash windows to meet the current energy requirements and comply with conservation area regulations. It also provides windows that are superior to the upvc window and door repairs options.

Sliding frames for windows made of sash were originally only used in large buildings or public buildings. However this changed as production became less expensive and craftsmen could create larger frames using more glass. By the late 18th century sash windows were the dominant wooden design in most British properties. Sash windows were simple to operate and allowed light to enter rooms without the use of curtains.

The early windows were made of plain glass However, by the 17th Century, sash windows began to become more attractive. They were initially made of colored glazing bars, also known as mullions. They were costly at first, but as glass production became cheaper and more efficient, they became an integral feature in many historic homes.

By the 19th century it was possible to make large, strong glass that didn't require support bars. This allowed the frame's size to be enlarged further, which allowed for a wider view out of the window. This was a significant advancement.

Another important improvement was the introduction of the double-hung sliding windows at the end of the I920s and beginning of the I930s. This allowed both the lower and upper sash to be opened simultaneously, and gave improved ventilation to the building.

The most commonly used type of sash is made from slow-growing deal (pine) however oak was used in the more prestigious buildings and in earlier examples. A parting bead is used to separate the two sashes. It is essential that it is maintained to prevent rattles and draughts. The sash pulleys, idler wheels and sash rollers also are crucial to the operation of the window.

2. Energy efficiency

Sash windows were replaced by hinged casements as clearer and larger sheets were made available. Glass plates were set in frames of timber that were rebated, then secured with glazing sprigs and putty was then sprayed onto the frame's two sides for watertightness. This form of glazing gradually superseded the leaded light bulbs.

The introduction of sashes led to the need for a wider range of ironmongery, with the most basic fittings being brass pulleys, lead (and later cast iron) weights, sash stoppers shutter hinges, knobs and shutters and a variety of fasteners to hold the sashes to their place. They were often decorated with motifs, inscriptions, and patterns engraved to identify the maker.

Sash windows can be extremely energy efficient when they are maintained regularly. However, if they are not maintained, they can become drafty and let in cold air. Paint and putty can cause draughts too. You can fix this problem by using wood-to-timber products.

The market for replacement windows is based heavily on the notion that older windows are beyond repair and therefore cannot be maintained economically. However, they can easily be maintained with a little attention. These repairs can be expensive and cause many disruptions in the home. To prevent this, many homeowners choose to replace their windows with PVC-u windows from one of the large "one stop shop" installation companies. They can replace all windows in a home in one day, thereby saving time and avoiding the need for various tradesmen to coordinate. These windows can be fitted with 'energy-saving double glazing to get higher energy ratings than traditional sash window. However double-glazed windows cannot replicate the section and proportions of historic timber sashes.

3. Security

It is possible to secure windows that are traditional without compromising their appearance. Ironmongery, such as sash chain, mortice bolts, and sash lock can be put in place. These can be installed in a way so that the window can be open for ventilation and cleaning. They are usually unobtrusive as they are designed to complement sash windows. They can be used alongside traditional sash-window catches and should be replaced with more robust models (such as those incorporating double screws) or sprung levers to reduce the possibility of them being hammered out.

Sash-window frames were traditionally constructed from slow grown deal or, in more luxurious homes made of oak. Where glazing bars have survived they should be preserved, and, if feasible, the wood of the cill should be replaced with the same wood. PVC-u companies often provide a one-stop shop installation service, removing and replacing windows on a complete house in a day without the need to engage other tradespeople, or coordinate visits from different suppliers.

4. Ventilation

When sash windows first introduced in the 17th century they allowed a substantial amount of light into structures. By the end 18th century, they had been modified so that more light could be let into rooms. Larger glass panes were also produced. The result was a lighter appearance and windows that were more elegant.

The introduction of sash windows also demanded an entirely new range of ironmongery. The first pulleys were made of wood, while later Victorian ones could be made of brass or a mixture of lead and wood, and there were many kinds of shutter hinges and knobs. These ironmongery elements should always be retained and cleaned down to ensure that the exquisite quality of their design can be appreciated.

To ensure they remain in good condition, timber windows require regular maintenance. Inattention to maintenance routinely could result in:

Sashes that do not move effortlessly.

Holes in the frame which allow water to enter and cause decay and damage.

break down of putty, allowing water to penetrate, which could cause decay in the frame and cill.

Steel casement windows gained popularity in the I920s & I930s because they were strong and slim, cheap and matched the trend of healthy living. Research has shown that softwood sash windows are just as efficient as PVC-u windows, and may even be more attractive.

The replacement upvc window renovation industry has done a great job convincing homeowners that their old windows were rotten drafty, noisy and beyond repair. The reality is that many older timber windows are in good shape and with minor repairs can easily be maintained for years to be.

5. Maintenance

The traditional sash windows need regular maintenance and inspection. If you don't maintain your window's sash, it could lead to the sash cords breaking and the glazing bars wearing out excessively. It could also cause the paint and putty to become damaged. The removal of the sashes could also result in structural movement within the frame that causes the sash to move out of alignment and not closing properly. The sash can also be stuck in its open position, allowing water and draughts to enter the building.

Damage to timber windows is often caused by water infiltration. This can be prevented by careful painting, regular repairs, and removing the source of dampness. The paint can be removed to expose the soft, decaying wood. The sections that are rotting must be removed with care and the affected area should be scarfed together or pieced together by using replacements of the same kind as the timber that remains. This method of repair increases the amount original fabric and is one of most non-invasive methods to treat the rot that occurs between timber and timber.

A wood condenser that is based on resin is a viable alternative to traditional sanding or staining. This is brushed onto the surface of the wood to stabilise and protect it from further damage. It is particularly useful in the treatment of pulleys and sash cords where it can help to prevent the breakage.

It is important to restore and not replace any historical ironmongery such as the sash latches and stays. These items are difficult to replace without damaging the quality of the original design. It is also recommended that modern fittings made of aluminium casement windows cambridge like sashlifts and chainstays, should be avoided since they can cause deterioration and corrosion of timber frames and sashes.