‘ The Rise of Passivhaus’
The basic principles of Passivhaus is its ability to reduce the permitted space heating demand and primary energy consumption. This is achieved in several ways, but primarily by designing a building envelope with high insulation with minimal thermal bridging. By adding the crucial element of fresh outdoor air being circulated with extensive heat recovery means that energy consumption is kept at a minimum. The best use of natural daylight, including some solar gain, further enhances the energy savings in this unique form of construction. The BRE refer to the following functional definition of Passivhaus:
“ A Passivhaus is a building, for which thermal comfort can be achieved solely by post-heating or post-cooling of the fresh air mass, which is required to achieve sufficient indoor air quality conditions – without the need for additional recirculation of air.”
Passivhaus is best known for its ability to offer very low energy consumption homes, typically just 15kWh / m2 / year, but the concept is being used increasingly on commercial buildings in the UK. It is claimed that the construction method can offer energy savings in use of up to 90 % compared to current UK building stock.
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