What is and what defines a Passive House?

Passive House is a leading international low-energy standard for the built environment, developed in Europe 30 years ago by Bo Adamson and Wolfgang Feist.  A building is a Passive House if it meets this international, voluntary, technical standard; regardless of climate zone (Cotterell & Dadeby 2012, p. 19). The standard is defined by the following 5 core technical requirements:

  1. Space Heating Demand must not exceed 15kWh annually or 10W per square meter of usable living space.

  2. Space Cooling Demand roughly matches the heat demand with an additional climate-dependent allowance for dehumidification.

  3. Primary Energy Demand must not exceed 120kWh annually for all domestic appliances (heating, cooling, hot water and domestic electricity) per square meter of usable living space. (Primary energy includes the amount of energy used to produce the energy at the source and deliver it to the home, a conversion factor of 2.6:1 is used in the PHPP to calculate energy delivered to the building).

  4. Airtightness is set at a maximum of 0.6 air changes per hour at 50 Pascals pressure (as verified with an onsite pressure test in both pressurised and depressurised states).

  5. Thermal Comfort must be met for all living areas year-round with not more than 10% of the hours in any given year exceeding 25°C.

Passive House Institute [PHI] (2014)

What are the benefits of a Passive House?

  • A Passive House is designed and constructed to be thermally comfortable and healthy.

  • A Passive House uses vastly less energy than conventional buildings, regardless of the climate zone. (A number of peer reviewed studies have shown up to as much as 80%).

  • Careful and considered design, informed by building physics means that buildings designed to meet the Passive House standard actually perform as modeled when constructed.

  • Thoughtful and careful construction by an appropriately skilled and motivated team leads to higher quality workmanship and consequently level of finish.

  • The quality and durability of materials and equipment is second to none.

(Cotterell & Dadeby 2012, p. 17)

Passive House and Aphi Projects?

As a Certified Passive House Tradesperson and holding a certificate of proficiency in Passive House Design, Dale Roberts’ leadership ensures the entire Aphi team understand and value Passive House principles. Every member of the Aphi team is passionate about Passive House and this is reflected in the quality of workmanship delivered. Professional relationships with Passive House Architects/Designers/Engineers, consultants, tradespeople and manufacturers, uniquely positions Aphi Projects to consult, source and deliver state of the art Passive House projects with the highest level of finish. 

Passive House and you?

Are you interested in how the home you live in affects your health and well-being?

Are you conscious of the impact you are having on the environment?

Do you appreciate that carefully considered design is critical in creating functional, beautiful buildings?

Contact Aphi Projects to discuss the design and building of your Passive House. 

Want to know more?

Here are some helpful websites and referenced texts  






Cotterell, J & Dadeby, A 2012, The Passivhaus Handbook, Green Books, Cambridge UK.

Passive House Institute 2014, Active for more comfort: Passive House, PHI, Darmstadt.