What are Passivhaus Standard Requirements?what is ph

The requirements for a home to meet Passivhaus Standards. The Passive House Institute detail these as follows:

  • Space Heating Energy Demand should not exceed 15 kWh per m2 of net living space per year.
  • The Renewable Primary Energy Demand, the total energy to be required for all of your home’s domestic applications, must not exceed 60 kWh per mper annum.
  • For Air-tightness, a maximum of 0.6 air changes per hour is allowed at 50 Pascals pressure (ACH50). This will be verified with an onsite pressure test.
  • Thermal comfort should be met for all living areas for energy-efficient houses in both summer and winter seasons. This shouldn’t exceed 25°c for any more than 10% of the hours in a year.
  • The "fabric first" concept of making sure the property is heavily insulated, is paramount - and generally to a much higher standard than current UK Building Regulations.

See our detailed blog regarding Passive House Standards as defined in the US/UK CLICK HERE

The image indicates the mechanical ventilation system [red and blue circuits] - in this example the fresh incoming air has been routed under the basement to pick up some 'heat' from the earth [in the winter] and to cool this same air in the summer - "Earth Heat Exchanger" A further method to reduce the total energy requirement of this design.

Also indicated is the summer sun entering the building via the windows, with suitable shading {roof overhangs] to prevent over-heating in the summer. However in winter, the lower sun will penetrate deeper into the structure, thus giving a valuable solar gain in these colder months.

The Basement will also be used for rainwater harvesting - to be filtered and used for flushing toilets and even bathing and showering etc. Thus reducing the cost of drinking water into the property.