Maintaining Timber Windows
A well-maintained timber window is a significant element of the historical fabric of a building. It illustrates in varying degrees the materials and technologies as well as the craftsmanship and architectural style of the time that it was built in.
If it is possible, repairs must be made in-situ. Repairing the worst areas of decay can be accomplished using proprietary resin-based systems.
Durability
Timber windows were made to last for hundreds of years. However, they need to be maintained to keep them looking good and functioning correctly. Maintenance tasks include sash cord repairs as well as tightening the sash pulleys and painting. The demand for enhancing windows made of timber to improve efficiency in energy use is also growing. This can involve replacing old glass units, fixing the window rebates that are in place or putting in new cills to allow for improved air sealing.
One of the main issues with traditional windows is the damage caused by corrosion of the paintwork. This is especially important when sash windows are concerned, as the gaps between sashes may be extremely large. In these instances water may get through the paint film and cause rotting of the putty and underlying wood. The rotting may be further aggravated due to weather conditions that are poor. To stop this from happening windows, they should be painted regularly using a suitable exterior wood paint.
The areas that are damaged should be repaired using resin-based products. This will ensure that the maximum possible amount of the original fabric remains. It is essential to limit the number of holes drilled into the frame in order to allow cable access, because they could let in moisture and cause decay.
The structural movement of the wall can also lead to distortions in the frame and the sash. This can lead to sash no longer fitting correctly, sticking or jamming in the opening and cracked glazing. This is often corrected by putting in new sash frames constructed of slow-growing deal (pine) or oak. The cill must be constructed of a durable hardwood like oak to avoid differential movement between the existing and new work.
To reduce the risk to reduce the risk of this happening, there are several companies that produce Boston pattern wooden sash that can be fitted into most openings. These sash are available in a variety of sizes and finishes that meet the needs of today's homeowner. These sash are coupled with quadruple draft strips and improved thermal insulation can significantly improve the efficiency of your home's energy usage.
Aesthetics
A lot of old timber frames have a high aesthetic appeal, as they show, in some form, the quality of the wood technology, the construction process, and the architectural style of the time they were constructed. They also may have significant historical value in their individual cases. This is especially true of early unglazed window openings in timber-framed structures, which were simply a series of openings within the frame, which were divided horizontally into mullions and iron or wood bars to deter intruders.
Traditional window joinery made of timber is a beautiful feature of a building and it is important to maintain its appearance. It is vital that any decay resulting from moisture penetration should be removed as soon as it is discovered. It is best to do this with thorough painting, especially if there has been damage or degradation. It is best to use paints designed to be used in a set (primer undercoat and finish) and follow the manufacturer’s recommendations for preparation and number coats at each stage.
The fungus that causes wet rot is able to spread quickly in old windows made of wood. To stop this from happening, remove any rotten or damaged parts as soon as you can. The replacement of rotting timber should be done with care and with a slow-growing deal (pine) and, whenever possible, the same species as that which is being removed to prevent differential movement between the new and old timbers.
Glass became less expensive and more abundant during the late medieval period and into the 17th century. In the process, glazed openings on timber-framed houses became more complex with moulded mullions, wooden tracery and cills that protruded deep. The glazing was increasingly placed within frames with rebates and pinned in by 'glazing sprigs' rather than into lead cames. This method of glazing is not just less susceptible to leaks, but also allows for larger clearer, more transparent sheets of glass to be used in the windows than would have been possible without the need for lead lights.
Energy efficiency
Traditional timber windows are energy efficient because of their thickness, multilayer construction and care for the smallest of details. They also have large glass areas and projection cills which reduce air infiltration. Windows can be designed to improve their energy efficiency with draught-proofing and secondary glazing. However it is essential to remember that such measures should be window replacement cambridge evaluated in terms of the overall integrity and appearance of the original window.
So, retaining existing historic windows that require repair instead of replacing them makes sense particularly when thermal improvements can be achieved cost-effectively through simple repairs and upgrades. Historic windows often have historical significance that demonstrates a range of technological advances and changes in architectural style. The pressure to replace these windows are generally based on the assumption that windows that are old will need to be replaced in the near future, but the majority of them are capable of providing service for 150, 200 and even 250 years if they are properly maintained.
It is crucial to recognize that the decay issues that are typical of windows made of timber can be avoided by regular maintenance and timely repairs. Additionally, it is essential to identify damp penetration problems and address them swiftly to prevent serious damage. Early deterioration of paint is a major problem since it allows moisture penetrate the wood and cause wet rot. The damage is usually not apparent until the paintwork is cracking or wavy but it can cause severe structural damage and lead to further decay.
A good paint will prevent 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 often water-resistant and may cause mildew to grow within the window frame.
The majority of older windows were constructed of sapwood-rich timber. The timbers will deteriorate rapidly if exposed to wet weather, but can be preserved with an extensive preservative treatment prior to when they are used. It is important to choose the right kind of wood for your location and climate, as these variables can affect the longevity of the joinery. Local window manufacturers produce a range of sash made of timber that can be customized to fit specific openings in historic buildings. They can be built to the standard Boston pattern dimensions, or to custom sizes that fit with historic buildings.
Maintenance
Regular inspection carefully redecorated, as well as timely repairs can prolong the lifespan of windows made of timber. The primary cause of decay is the infiltration of moisture through deteriorated paint and putty. This can be prevented by using a high-quality wood preservative and thoroughly painting the wood.
It is essential that repairs to old sash and casement windows are well executed and done without causing any disturbance. It is possible to repair many traditional timber window designs without having to remove the frame. This should be done as often as is feasible. Paint that is peeling or loose should be removed carefully and lightly sanded to improve the 'key' of the surface, allowing for an easier adhesion of the new coating. It is essential to avoid removing old paint layers that may have historical significance.
When a section of wood has rotted, 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 inserted should be treated with wood preservative and the joint between the cill for timber and the sub-cill of the masonry should be sealed.
It can be tempting to replace traditional windows with PVC U, particularly when the installer offers an 'all-in-one' installation which includes removal and replacement in one day. It is essential that installers of replacement windows are aware of the history and construction of traditional timber frames. This will enable them to make the right suggestions for improvements to energy efficiency and other technical upgrades that do not alter the character of a historic building. The window installers who provide replacement windows must be registered with a Competent Persons Scheme such as FENSA. This will ensure the replacements are deemed to be approved under Building Regulations as a suitable option. A skilled carpenter is able to install PVC-u windows that are suited to the original character of the building. This is particularly true when the windows are located within listed buildings or conservation areas.