Many historical property owners view repairing sash windows as problematic, as they automatically associate the repairing and renovation of traditional box sash windows with a radical change of the building’s exterior and a diminishment of character, which in this case they normally want to preserve.
However, contrary to common perception, sash window repair is a very particular procedure, purposely designed to meet modern quality and performance standards and at the same time preserve the historical charm. After having stood the test of time for centuries in some cases, old sash windows will most likely have to be repaired to some extent, adding to that the improvements needed in order to make them more practical.
Below are some of the most common problems sash window owners encounter:-
Operational difficulties: There are many possible causes for stiff or sticking windows, which require additional effort to operate, such as a warping or swelling of the wood, or alternatively, a build-up of paint or dirt, most commonly paint.
Broken parts: It is not uncommon at all for any part to be weakened by usage or time, especially when sash windows are over a hundred years old. All broken parts can be replaced, usually in a manner which does not affect the overall appearance of the windows.
Damaged sashes: Akin to the glass panels of casement windows, those of sash windows are frequently broken or cracked as well, but can easily be replaced by specialists, regardless of their type or size.
Wood rotting: This is usually specific to the exterior of the box, particularly the bottom rail, which tends to show the earliest signs of wood decay. However, it may be affected on a superficial level and fairly easy to fix by applying certain wood treatments.
Paint deterioration: The durability of any paint application is limited, therefore in time there will be flaking, peeling and dirt sediments which cannot be removed. In order to achieve optimal preservation, sash windows have to be repainted on a regular basis, typically every five years.
Fragmented putty: Like paint, putty is a material with limited endurance and after a number of years it begins to darken and chip away. That can be solved by a specialist by carefully removing the old damaged putty and replacing it.
Poorly fitted sash weights: Although modern sash windows use a different operational method, classic types are operated through a weights and pulley system, where the weights are central in ensuring perfect balance. Since this is an long-standing mechanism designed centuries ago, few current owners are familiar with its requirements to a fine detail. Hence old weights can often be non-concordant with the rest of the window (especially if parts have been replaced), unbalanced or aligned improperly.
Damage caused by unprofessional repairs: Due to the fact that sash windows require particular care, repairs and renovations should always be carried out by qualified sash window repair companies. Otherwise, a number of malfunctions can occur. The most common problem develops following painting jobs, when excess paint dries and causes windows to stick. Furthermore, non-professionals tend to have difficulties matching the right replacement parts and buy unsuitable types or sizes – even the slightest size mismatching can make windows difficult to operate. Amateurish draught proofing is also unadvisable as it is ineffective and can be difficult to remove, depending on the material used.
Sash windows in need of repairs usually show signs of wood degradation, particularly rotting, but also warping or swelling in some cases. That does not, however, mean that the windows are condemned, as they can be restored to their initial beauty, provided that the damage is not to extensive. For a superficial level of decay, wood is treated using a two-part epoxy resin, whereas for irreparable damage, parts of the frame will have to be replaced. Nonetheless, that seems to happen more when buildings are abandoned and not tended to at all, as most owners notice the decay in its incipient phase, in good time to opt for a repair before having to consider a part or window replacement.
There are many reasons to do so, of a practical as well as a sentimental nature. Besides the historical value of the wood the original sash box was constructed from, owners should be aware of its durability, although the issue can seem paradoxical to some as they associate age with weakening and corrosion. The reality is that in past centuries joinery items were hand made, unique and perfected with meticulousness, using very good quality hardwood as prime matter. No modern technology can substitute that diligence when comparing hand carved wooden sash boxes to mass-produced ones, particularly those made from plastic, which are only guaranteed to last for a decade by most manufacturers.