What is a Passive House?
A Passive House is a building in which a comfortable interior climate can be maintained without active heating and cooling systems. The house heats and cools itself, hence “passive”. For passive construction, prerequisite to this capability is an annual heating requirement that is less than 15 kWh/(m²a) not to be attained at the cost of an increase in use of energy for other purposes (e.g., electricity). Furthermore, the combined primary energy consumption of living area of a European passive house may not exceed 120 kWh/(m²a) for heat, hot water and household electricity. The combined primary energy consumption of living area of a standard house is approximately 220 kWh/(m²a) for heat, hot water and household electricity. External Links for more information: www.passiv.de and www.europeanpassivehouses.org
Passive House Design – Main Features
The main design features of passive homes include: –
- Positioning of homes and buildings to avail of free solar energy. Orientation and selection of the correct site for your home is imperative. Proximity to and height of adjoining buildings can reduce your solar gain.
- Higher levels of insulation help reduce the cost of heating.
- Air tightness of your home is crucial in keeping all that free solar energy within the home.
- Locating the majority of your windows on south facing elevations and reducing the size of any north facing windows.
- As your home is now extremely air tight, mechanical ventilation will need to be introduced. By ensuring that this ventilation has heat recovery the incoming fresh air shall be preheated by the extracted air. This simple measure helps keep your home warm without having to reheat the fresh air.
- Correct detailing of junctions between the external fabric and windows and doors to reduce heat loss.
- Introducing solar panels will help produce approx. 70% of your required hot water once sized correctly and positioned to face south to optimise the solar gain.
- Other simple measures such as using A rated kitchen appliances and fitting low energy light bulbs will help ensure your new home is both comfortable and warm to live in