Design Buy Build Issue 34 2018 | Page 12

‘ 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 .
12