How to Restore Timber Sash Windows in Cambridge
Many homes in Cambridge have traditional sash windows and homeowners are proud of how they look. However, sash windows may become stuck and difficult to open or close. This is usually due to moisture which can cause the wood to expand.
Box sash windows were historically operated by chains or cotton cords, as well as lead weights. Modern windows with sash springs are concealed to solve this problem.
1. Aesthetics
Timber sash windows, unlike PVC-u windows that are made in imperial sizes that are modular, are able to be restored to original dimensions. This allows the restoration to be in line with modern energy requirements while still complying with conservation areas regulations. It also provides an option that is superior to the uPVC options.
Sliding frames for windows made of sash were originally only used in large buildings or public buildings. However, this changed when production became more affordable and artisans could make larger frames using larger glass. In the late 18th century Sash windows were the most popular wooden style in a majority of British properties. As they were easy to open sash windows allowed light into rooms without curtains.
The first windows were made of clear glass however, in the 17th century the sash windows began to become more ornamental. They were initially made of colored glazing bars or mullions. They were costly at the beginning but as glass production became cheaper and more efficient, they became commonplace in many period houses.
By the 19th century it was possible to manufacture large, sturdy glass that did not require supporting bars. This allowed for the frame to be made larger and, in turn, gave an improved view. This was a significant innovation.
Another significant improvement was the introduction of the double-hung sliding window at the end of the I920s and beginning of I930s. This allowed both the lower and upper sash to be opened simultaneously, and gave improved ventilation to buildings.
The most commonly used kind of sash is made from slow-growing deal (pine) however oak was also used in more luxurious buildings and in some earlier examples. It is crucial to maintain the separation bead that is used to separate the sashes. This will help prevent rattles and draughts. It is also crucial that sash pulleys and idler wheels are kept in good shape as they aid in operating the window.
2. Energy efficiency
As larger and clearer sheets of glass were made available, sash windows began replacing hinged casements. Glass plates were set in frames of timber that were rebated, then pinned with glazing sprigs and putty was sprayed on the frame's sides for watertightness. This kind of glazing gradually superseded led lights.
Sashes were introduced, which led to a greater demand for ironmongery. The basic fittings included brass pulleys (and later cast-iron) weights as well as sash stoppers shutter hinges, handles and shutter hinges, and a variety of fasteners to secure the sashes. These were usually decorated with designs, inscriptions, and patterns engraved to identify the maker.
With regular maintenance, sash windows can be very energy efficient. However, if they are not maintained, they can become draughty and let in cold air. Putty and paint can cause draughts too. It is possible to fix this issue 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 double glazed window cambridge can be maintained with a little attention. Repairs can be costly and cause lots of disruption to the home. To avoid this homeowners, many 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 house in a single day, saving time and avoiding the need for various tradesmen to coordinate. These windows can be fitted with 'energy-saving' double glazing to achieve higher energy ratings than the traditional windows with sash. However, these double-glazed units 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 like sash chain, mortice bolts and sash lock could be put in place. They can be fitted in such a way that the window can be open for ventilation and cleaning. These products are usually unobtrusive, as they are designed to fit the sash window. They can be used in conjunction with traditional sash-window catches that 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 are typically made from oak or slow-grown deal. If the glazing bars remain intact and in good condition, they should be kept. Where possible, the timber cills should be replaced by wood that is in line with. PVC-u companies often offer a one stop shop installation service, removing and replacing windows on a complete house in a day without the need to involve other tradespeople or co-ordinate various visits from different suppliers.
4. Ventilation
Sash windows were introduced in the 17th century and allowed for a large amount of light into buildings. By the end of the 18th century, they were adapted to allow more light into rooms and bigger glazing panes started to be manufactured. The result was a much more streamlined appearance, and windows with a higher degree of elegance than before.
The introduction of sash windows also required the creation of a new line of ironmongery. Early pulleys could be made from wood. Later Victorian ones were made of brass or a mix of leaded and wood. There were also various types of shutter hinges and knobs. These ironmongery pieces should be kept clean and preserved in order to appreciate their beautiful design.
To keep them in good condition, timber windows require regular maintenance. A lack of attention to them regularly could lead to:
sashes that no longer slide easily.
holes in the frame allow water causing damage and decay.
break down of the putty and allow water to penetrate, which can lead to decay in the frame and cill.
In the I920s and the I930s steel casement windows grew in popularity due to their durability slim and affordable and also matched the fashion for healthy living. However, research has proven that traditional softwood sash windows are as thermally efficient as double-glazed windows made of PVC-u, and are more attractive than the modern sleek design of casement windows.
The replacement window industry has made a significant effort to convince homeowners that their traditional windows are rotten, draughty and beyond repair. Many old timber windows can be fixed and utilized for a longer period with minor repairs.
5. Maintenance
The traditional sash windows require regular maintenance and inspection. Inability to maintain it properly can lead to the sash cords breaking, a lot of wear on the glazing bars, and deterioration of paint and putty. The removal of sashes can also result in structural movement within the frame, which can cause the sash not to close correctly. It is also possible for the sash be stuck or fixed in the open position and this can let water and draughts in the property.
The damage to timber windows is often caused by moisture penetration. This can be avoided with regular maintenance, thorough painting and removing the source of dampness. Wet rot is recognisable by the wavy look of the existing paint which can be removed to reveal rotting, soft timber. Any rotten sections of timber should be cut off and the affected part carefully wrapped or pieced back using replacements made of the same type of wood as the ones remaining. This repair method increases the amount of fabric used in the first place and is one of most non-invasive methods to treat wood-to-timber rot.
The use of a resin-based wood consolidant is another alternative to the traditional method of staining and sanding. This is brushed onto the surface of the wood to help stabilize it and protect it from further damage. It is particularly useful in the treatment of sash cords and pulleys which help stop breakage.
It is crucial to restore and not replace any historic ironmongery such as sash latches and stays. It is difficult to replace these items without altering their original design. It is recommended that the use of modern aluminum fittings, such as chain stays and sash lifts is avoided whenever feasible as they could cause corrosion and damage to frames and sashes made of timber.