Passivhaus or 'Passive House' is an energy performance standard for dwellings, commercial, industrial and public buildings that can be adopted throughout the world. It is intended primarily for new buildings, although it can be applied to refurbishment projects.
Passivhaus suggests that, '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.’ This means that a traditional heating or cooling system is no longer essential.
The Passivhaus standard can be achieved by measures including:
- Pre-cooling of the supply air
- Night purging
- Natural ventilation
- Mechanical ventilation heat recovery (MVHR)
- Avoidance of thermal bridges
- Passive solar gains
- Exploitation of internal heat sources
Whilst Passivhaus adopts the principles of passive design, it differs in its imposition of an overall limit on primary energy consumption. This limit includes; domestic hot water, lighting, projected appliance consumption, space heating, fans and pumps.
The primary energy demand target must be met in all cases, and either the specific heating demand target or the specific heating load target must be also met. In addition, there are limiting values for the performance of the building fabric, doors and glazing, ventilation systems, air tightness levels and thermal bridging, which is why SIPS technology is ideally suited to Passivhaus construction requirements.
The energy balance of the proposed building must be verified using the Passive House Planning Package (PHPP). Certification is available from the Passive House Institute (PHI) for buildings, building components, designers, consultants and tradespersons.