The uniqueness of Passive House (Passivhaus)
Passive House homes are a combination of comfort and ultra-low energy use. The key elements of Passive House buildings include high performance windows, continuous high level of insulation, air-tight construction, thermal bridge free construction, and mechanical ventilation with heat recovery. Appearance wise, Passive House can be adapted to any architectural style. Passive House is a performance standard which does not prescribe a specific construction method. It must meet specific energy demands, whilst designers can choose the best construction method to meet these targets.
Increased comfort, less energy consumption
With Passive House buildings careful planning and procurement is critical. Attention to detail is paramount to ensure a minimal energy demand, with the heat of four people (or 10 tea light candles) being able to keep an area of 20 m² in the height of winter warm, even in extremely cold climates. In practice a Passive House is not heated with tea lights; however, the equivalent energy use is used with efficient heating systems in combination with mechanical ventilation with heat recovery. And in Summer Passive House homes provide great comfort levels, with no or little reliance on air conditioning. Thus, with a Passive House the energy needed for heating and cooling is extremely low.
What makes Passive House unique?
The Passive House has five principles, which are:
• Continuous high-level of insulation
• High performance window frames and glazing
• An airtight building envelope
• Mechanical ventilation with heat recovery
• Thermal bridge free design and construction
Adaptability to local climates
The Passive House Standard has been used worldwide with the general methodology being the same whilst each project will have individual components that respond to the local climate. For example, to ensure comfort during hot periods in warmer climates greater attention is given to passive cooling, with shading devices and natural ventilation. Thus, each Passive House building will have individual characteristics that are optimised to the local climate.
Ultra-low energy is the key component of Passive House. And, over the course of a year, a Passive House building uses no more than 15kWh, which is equivalent to 1.5 litres of oil per square meter of internal space. This is a reduction of 90 percent energy use for heating and cooling, when compared to a standard building.
Reducing energy requirements further
To further reduce the energy use it is important to use efficient electrical appliances. Whilst to run the mechanical ventilation with heat recover is negligible with it being roughly 2 kWh/m², which is less than an LED light bulb.
Where it all began
The Passive House Standard was born out of a conversation between Wolfgang Feist and Bo Adamson, who asked themselves how buildings could be created in a sustainable, ultra-low energy way. This resulted in research that led to the first Passive House being completed in 1991, which provided a built example of ultra-low energy, with comfort, affordability, and excellent indoor air quality. The building was a row four terrace houses, which still preforms as it was planned. With the annual energy use being consistently less than the prescribed 15 kWh per square metre of habitable space.
Future-proofing your home
Since 1990, the uptake of the Passive House Standard has been huge, and as of 2016 there have been approximately 60,000 buildings completed world-wide; whilst the popularity in Australia is rapidly increasing with 100s of buildings in the design and construction phase. Building a Passive House is not only a sound investment, it simply makes sense.
The super-insulated continuous envelope of a Passive House keeps the indoor temperatures at a comfortable level, just as a thermos does for keeping drinks at a pleasant temperature. During all seasons Passive Houses maintain a consistent temperature on internal surfaces and air, without temperature extremes or draughts. Whilst, the building’s mechanical ventilation with heat recovery allows for constant fresh high-quality air at room temperature.
With ultra-low energy use, Passive House minimises the use of limited resources like gas and oil. And, they make the use of renewable energy more affordable with the demands being less, for example you would require less photovoltaic panels than a standard build as your energy demands will be minimal. Passive House ultra-low energy use significantly reduces CO² emissions and provides a positive contribution to minimising climate change.
Passive House is a contemporary innovative building standard that is creating new insights for architects and engineers. Industry responses are positive, with market forces driving economics and innovation, with highly efficient products being created.
Since the first Passive House building was built in 1990 there has been over 60,000 projects completed and have had outstanding performances. Several hundred of these being monitored and tested, with consistently positive results.
To achieve Passive House ultra-low energy levels high quality building physics are used, with the three key aspects of continuous high-level of insulation, airtight building envelope, and thermal bridge free construction. This results in Passive House buildings having a structural longevity, with ultra-low risks of condensation within the building structure (and interiors).
Passive Houses are uncomplicated and user-friendly, and don’t require user manuals to operate. And, they provide comfortable temperatures, no draughts, and fresh air. Passive Houses has no complicated technology and are user-friendly.
The Passive House Standard is a voluntary ultra-low energy standard, with people being drawn to it for its benefits and simplicity. It can be built by anyone and it makes a sustainable contribution without compromising on comfort, with construction products and the Passive House Planning Package (PHPP) software being accessible. Whether a Passive House has a basic or unique design, it is always something special.
Economics and Affordability
Passive House projects are high performance and high-quality buildings, where the initial investment costs are higher. This is due to the additional design input and superior building components. However, over the building’s life span they are more cost effective than your standard build, due to the low running costs.