In Australia, particularly in Darwin and the surrounding region, keeping our living spaces cool and comfortable can sometimes be quite a challenge. Insulation and climate control devices work well with keeping a stable temperature inside, but the downside is that they often cost a lot to run, and are only effective while they’re running, with the cool air that you’ve just paid for escaping through the gaps in your insulation, off into the outside world. Many sustainable design and building practices have emerged over the years and one which interests me especially is Passive House design (which fits perfectly with my love for Biophilic Design!). The potential for excellent interior design coupled with a stylish eco-friendly architectural design is a winning combination!
Passive House is a design and construction philosophy, which first originated in Germany in 1990 through a conversation between Bo Adamson of Lund University, in Sweden, and Wolfgang Feist of the Institut für Wohnen und Umwelt (Institute for Housing and the Environment). The Passive House philosophy is based on solid science with the aim of reducing excess energy usage in any kind of building, in any climate, increasing the comfort and functionality of our buildings in the process. Passive House designs can reduce household energy consumption by up to 90% compared to traditional building methods, while maintaining high levels of comfort and environmental control. The inside of a passive house is designed to keep a constant temperature throughout the building, with expected indoor temperatures ranging between 20-25 degrees Celsius. This is achieved without the use of heating or cooling systems, drastically reducing the amount of energy required for comfortable indoor living, by using ‘passive’ influences, as the name suggests, such as utilising the sunshine, shade and ventilation to achieve comfortable temperatures.
The Passive House philosophy can be broken down into five design principles, all of which rely on each other in order to achieve the desired results:
Superinsulated Envelopes
Higher than normal levels of insulation, using low-conductivity materials, ensuring that the building is wrapped in insulation as tightly as possible, to make the building air-tight and to ensure that warm/cool air isn’t being sapped away by the materials that the building is constructed from.
Air-Tight Construction
Having an air-tight construction is imperative to the Passive House philosophy, as it adds greater control over the interior climate, by limiting uncontrolled air exchange with the exterior of the building. While air exchange is necessary for ventilation and providing fresh air, it is far more effective to control air exchange by tightening the envelope and using mechanical ventilation.
High-Performance Glazing
Windows play a huge role when it comes to heat loss/gain, so double or even triple glazed windows are used, constructed out of non-conductive materials and filled with Argon or Krypton gas to provide further insulation.
Thermal Bridge Free Detailing
A thermal bridge is a part of the building where architectural features meet, for example, how windows are attached to walls, how a wall meets a balcony and how walls meet corners. Reducing direct conductive connections between the interior and exterior is important.
Heat Recovery Ventilation
Passive House designs are airtight, so a ventilation system is required to bring in fresh air and exhaust out pollutants such as CO2 and moisture. Inbuilt to the designs are heat recovery ventilators to continuously remove stale or moist air and replace it with fresh air. The HRV extracts heat from the exhaust air and puts it into the fresh air that it is replacing it with. These HRV systems recover around 75% of the heat that has been extracted during the purification process.
All of these design principles can be used together to create a living space that is not only comfortable, but stylish and far better for the environment than traditional construction styles. The Australian climate can be harsh and extreme at both ends of the spectrum, with sweltering summers and freezing winters. Both summer and winter are becoming more extreme as time goes on and climate change further impacts our lives. A Certified Passive House can help to shelter you from the weather extremes, creating a comfortable environment for you to live in, as well as drastically reducing your energy bills and carbon footprint.
Does Passive House design excite you as much as it excites me?! Let’s talk about putting a plan together to follow the philosophy of Passive House to create a space that’s not only good for the environment, but also stylish with unlimited potential!
