Maintaining Timber Windows
A well-maintained and maintained timber window is an important element of the historical fabric of a building. It reflects in different degrees, the materials and techniques of the time period it was made, the architectural style and craftsmanship.
When possible, repairs should be made on-site. Repairing the worst areas of decay can be accomplished by using specialized resin-based systems.
Durability
The windows made of wood in many historic structures were designed to last for a long time. But, they have to be maintained to keep them looking great and working properly. The most frequently-asked maintenance tasks include repairs to sash cords and re-tightening the sash pulleys and painting. There is a growing need to upgrade the timber windows to improve energy efficiency. This could include replacing old glazing units, fixing the window rebates that are in place or installing new cills for improved air seal.
The deterioration of paintwork is a major issue with traditional windows. This is especially important where windows with sash are involved since the gaps between the sashes can be very large. In these cases water can enter the paint film and cause rotting of the putty or wood beneath. The weather can be a factor in accelerating the rotting. To avoid this windows from becoming rotten, they must be painted regularly using a suitable exterior wood paint.
Corroded areas should also be repaired using a resin-based product. This will ensure the maximum amount of original fabric is retained. It is also important to minimise the number of holes drilled into the frame to allow cable entry as these can admit water and lead to decay.
The wall's structural movement could also cause distortions in the frame as well as the sash. This could result in the sash not fitting properly and jamming or sticking into the opening, and broken glass. This can be corrected often by fitting new frames for sash made of slow-growing deal (pine), or oak. The cill should be constructed from durable hardwood such as oak to avoid differential movement between the existing and new work.
There are a variety of companies that produce Boston pattern wooden sash that fit most existing openings. These sash are available in a range of sizes and finishes that meet the needs of the modern homeowner. Combined with quadruple draught strips and better thermal insulation these new sash options can make a substantial difference to the energy efficiency of a house.
Aesthetics
Many old timber windows have a high aesthetic value since they usually demonstrate, in a way, the materials and technology and architectural style of the time in when they were built. They may have significant historical value in their own right. This is especially true for windows that were unglazed in the early days of timber framed buildings which were just a collection of openings within the frame, which were divided horizontally into mullions, and vertically into wood or iron bars to keep out intruders.
Traditional window joinery made from timber can be a stunning feature of a building and it is important to maintain its appearance. As soon as you see any signs of decay due to water penetration it is essential to stop it. It is recommended to do this by thorough painting, especially if there is damage or deterioration. It is recommended to use paints that are designed to be used as part of a system (primer as well as undercoat, finish and primer) and follow the manufacturer's instructions in terms of preparation and number of coats required at each stage.
Wet rot is a typical problem for older timber windows. The best way to stop it becoming a problem is to take out any damaged or rotten sections immediately to stop the spread of the fungus that causes it. The replacement of wood that is rotting should be carefully undertaken with a slow-growing deal (pine) window repairs cambridge and, whenever feasible using the same species as that which is being removed to prevent shifting between the new section and existing timbers.
In the late medieval and 17th century periods glass became cheaper and more abundant, and the openings for glazed glass in timber-framed buildings gradually became more sophisticated, with tracery made of wood as well as moulded mullions and projecting cills. In recent years, glass was fixed into rebated frames with glazing sprigs instead of lead cames. This method of glazing not only makes windows less likely to leak, but also allows for larger sheets of glass to be employed than would be possible without the use of lead lights.
Energy efficiency
Traditional timber windows are energy efficient because of their thickness, multilayer construction and care for particulars. They also feature large glass areas and projection cills which reduce air infiltration. Windows can be designed to increase their energy efficiency through draughtproofing and secondary glazing. It is essential to remember that these measures must be considered in relation to the overall appearance and integrity of the original windows.
As a result, retaining the existing windows from the past that are in need of repair instead of replacing them is sensible particularly when thermal enhancements can be achieved inexpensively with simple repairs and improvements. Older windows typically have historical significance that illustrates a variety of technological advancement and changes in architectural taste. Many people believe that these windows will have to be replaced in the near future. However, they can still provide service for 150,200, and even 250 years if you take care of maintenance.
It is crucial to understand that decay issues associated in traditional timber windows are avoidable with quick and thorough repairs. It is also important to recognize damp issues and address them promptly so that you can avoid serious damage. The early deterioration of paint can be a problem because it allows moisture to get into the wood, which can cause wet rot. This damage is often not evident until the paintwork becomes cracking or wavy however, it can cause serious structural damage and lead to further decay.
A quality paint will block moisture penetration. To prevent mould and condensation, it is important to keep the paintwork as clean as possible. Modern synthetic paints are problematic because they are water-resistant, and can cause mildew to develop within the window frame.
Most older windows were made from sapwood-rich wood. These timbers deteriorate quickly if exposed to rain, but they can be protected with a thorough preservation process prior to use. It is essential to select the right kind of wood for your location and the climate, since these factors will affect the durability of the joinery. Local window manufacturers make various types of timber sash that can be customized to fit specific historic openings. They can be produced in the standard Boston pattern or in custom sizes that can be adapted to historic buildings.
Maintenance
Regular inspections as well as careful redecoration and prompt repairs can extend the lifespan of windows made of timber. The main reason for decay is the infiltration of moisture through deteriorated paint and putty. This can be avoided by careful painting and the use of a good quality wood preservative.
It is important that repairs to the old sash and casement windows are properly executed, and carried out without causing any disturbance. It is possible to repair the majority of traditional wooden window designs without removing the frame. This should be done as often as is feasible. Loose or peeling paint should be removed with care and sanded lightly to improve the key of the surface and allow for an improved adhesion of the new coating. It is crucial to avoid removing old paint layers, as they may have historical value.
When a section of wood is decayed, the best solution is to take it off and replace it with timber inserts that are shaped to match existing profiles. The wood that is being inserted should be treated with a wood preservative and the joint between the cill for timber and the masonry sub-cill should be sealed.
It is tempting to replace traditional windows with PVC U, particularly when the installer offers an all-in-one installation that includes removal and replacement in a single day. It is, however, vital that the installer of windows replacement has a thorough knowledge of the construction and history of traditional wooden frames. This will enable them to make the right recommendations for energy efficiency improvements as well as other technological upgrades that won't alter the appearance of a historic building. Window replacements should be registered with a Competent Persons Scheme such as FENSA. This will ensure the replacements are deemed acceptable in accordance with Building Regulations as a suitable option. A skilled carpenter can put in PVC-u windows that are suited to the original building's style. This is especially relevant when windows are situated within conservation areas or listed buildings.