1st April 2015


Draught Proofing Windows And Doors

Draught-proofing is one of the most cost effective and least intrusive ways of improving the comfort of occupants and reducing energy used for heating with little or no change to a building’s appearance. It has the added benefit of helping to reduce noise and keeping out dust. Recent research has shown draught-proofing can reduce air leakage in windows by between 33% and 50% significantly reducing the energy requirement needed for heating the room.



Insulating Dormers



Slim Line Double Glazing



Secondary Glazing For Windows

Older windows can often be draughty as over time they distort as joints become weakened. Although adequate ventilation is important in older buildings excessive air leakage through windows wastes heat and is uncomfortable for occupants. Carefully designed and installed secondary glazing allows the original windows to be retained unaltered, and where necessary repaired, whilst reducing air leakage and conducted heat losses.

Recent research has shown heat losses by conduction and radiation through a window as a whole can be reduced by over 60% by using secondary glazing with a low emissivity (low-E) hard coating facing the outside. The research has also shown that further savings can be made if the secondary glazing uses insulating frames or incorporates double or vacuum glazed units. Besides increasing the thermal performance of windows secondary glazing unlike double glazing can have a number of other benefits including being highly effective at reducing noise transmission.



Traditional Windows: Their Care, Repair and Upgrading

The loss of traditional windows from our older buildings poses one of the major threats to our heritage. Traditional windows and their glazing make a hugely important contribution to the value and significance of historic areas. They are an integral part of the design of older buildings and can be important artefacts in their own right, often made with great skill and ingenuity with materials of a higher quality than are generally available today. Furthermore, the distinctive appearance of antique hand-made glass is not easily imitated in modern glazing. Windows are particularly vulnerable elements of a building as they are relatively easily replaced or altered. Such work often has a profound affect not only on the building itself but on the appearance of street and local area.

Traditional windows can be simply and economically repaired, usually at a cost significantly less than replacement. For timber windows this is largely due to the high quality and durability of the timber that was used in the past (generally pre-1919) to make windows. Properly maintained, old timber windows can enjoy extremely long lives. It is rare to find that all windows in an old building require new sections. Many historic components continue to give service after 150, 200 or even 250 years. Traditional metal windows can also usually be economically repaired and their thermal performance improved, avoiding the need for total replacement.

The whole-life environmental costs of replacement will be much greater than simply refurbishing. It will take many years before savings on heating offset the large amounts of energy used to make PVC-u windows in the first place. Repairing traditional windows rather than replacing them is not only more sustainable but makes better economic sense, particularly when the use of shutters or secondary glazing to improve their thermal performance is taken into account.