It means that for the first time low-e glass will effectively be mandatory for all new and replacement windows.
Although the final details have not been published yet, Part F is likely to include some radical changes that will have a significant impact on glazing specifications in Northern Ireland. While the changes will be far-reaching, the use of Pilkington K Glass should ensure all windows satisfy the requirements. An additional benefit is that as a hard coated product it is tough, durable and easy to process.
The introduction of the new requirements will bring with them some fundamental changes for both new and replacement windows. Primarily, for new buildings, compliance will be achieved on the basis of the total CO2 performance of the whole building. However there will be worst-case U values that individual elements have to achieve. For windows this will be 2.2. This maximum window U value means that ordinary double-glazing will no longer be permissible in new buildings.
The most radical change however will be the requirement that all replacement windows installed in existing buildings must achieve a minimum performance level. In housing the replacement window U value will have to be no greater than 2.0. However, the introduction of a new system, the Window Energy Ratings (WERs), creates an alternative route to compliance. A replacement window achieving a band E will be acceptable. Again this can be accomplished by windows containing Pilkington K Glass.
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