Our time working with the City of Edinburgh Council (CEC) inspired SAV Systems to undertake Passivhaus certification. CEC has set ambitious targets to achieve Net Zero by 2035, leading the council to apply passive house design principles to all their new schools. The core philosophy of passive house design is to create a comfortable and energy efficient building with minimal energy wastage, raising the standard of the buildings it is applied to.

Ventilation plays a crucial part in two requirements of passive house standards: air tightness and space heating demand. Openings in buildings, such as windows and porous building materials can allow heat to escape, wasting the energy generated by the building. Consequently, Passivhaus buildings have high airtightness and low heat loss. However, in increasing the airtightness of a building to conserve energy, indoor air quality can suffer. Therefore, a mechanical ventilation solution is required to manage indoor air quality without wasting energy.

There are a range of approved MVHR solutions available under the Passivhaus framework. Many of these are centralised systems, which normally have high specific fan powers. AirMasters are decentralised and air distribution is duct free, so fan power is kept to a minimum. A typical classroom installation requires one AirMaster AM 1000 per room with intake and exhaust connection to outside. The AM 1000 can recover up to 90% of the room’s heat using an aluminium heat exchanger, reducing the building’s heat load and heat loss.

The certification of the AM 1000 makes available an innovative ventilation strategy that can improve indoor air quality without sacrificing thermal comfort. Not only is this certification exciting for SAV Systems, but it is also exciting for decentralised mechanical MVHR as a ventilation strategy. With growing pressure on buildings to become energy efficient and comfortable, decentralised MVHR like AirMaster will play a vital role in the solution.