Keeping Heat Inside
It is important to ensure that you do not lose the heat from your home through your windows. Efficient glass will enable you to reduce energy costs, make your home more comfortable and reduce the carbon emissions which will damage the Earth's atmosphere. Pilkington have been at the forefront of development of glass products which enable this to be achieved. The Government introduced legislation in 2002 in England and Wales to try to reduce the loss of energy from the nations' buildings. The change and subsequent legislation means that new home and replacement windows and extensions in existing homes, must now achieve defined energy efficiency standards. Similar legislation is also in existence in Scotland and the Republic of Ireland, and is expected in Northern Ireland during 2006.It is possible to assess how efficient a window is at stopping heat escaping by looking at its so called U-value. However, this does not take into account heat coming in from the sun. Solar energy will improve the overall benefit that the window will provide. The recently introduced Window Energy Rating (WER), is a grading of the window on a similar energy efficiency scale as seen on domestic appliances. Windows with D rating can meet the Government's requirements and those with C, B or A, have increasingly better performance.
The type of glass used in the insulating glass units in energy efficient windows is generally know as 'low emissivity' or low-e glass. Generally, the improvement over ordinary glass is made by applying a fine coating to the glass. The more well known and trusted low-e product is Pilkington K Glass™. Other products are available which have a better U value such as our own Pilkington Optitherm™. However, such products achieve only comparable WER ratings due to the ability of Pilkington K Glass™ to allow the sun's heat through at the same time as stopping heat escaping.
When these products are incorporated in Pilkington Insulating Glass Units (IGUs) these are known as Pilkington Insulight™ Therm.