PASSIVE HOUSING LANGUAGE
Passive Housing Language - Third Skin. Design strategies and movement within the 1960s Passive House is a global building standard which sets performance levels for the comfort and energy performance of houses. Ultimately the standard is about achieving adequate comfort within a design without the need for action or energy. Its principles is to be able to control solar radiation which can be captured or avoided during specific times of the year to maintain comfort within the built environment. It avoids the use of artificial heating and cooling. Basic design principles such as allowing winter solar radiation to heat spaces or surfaces to provide additional heating to the space. During the summer
months this same radiation can be blocked using shading devices reducing unwanted heat gain. (Barnett, n.d) Key principles of the use of insulation which prevents thermal conductivity between the building envelope and the external environment. A building envelope and each material within the envelope will have a U-value (thermal transmittance), the lower this value the less heat transfer occur through the building. A lower U-value will assist in providing a comfortable environment without additional heating and cooling. Thermal mass can also be used to “store and radiate heat over time”. (Barnett, n.d) As explained there are limitations to a passive approach. These include decreasing life expectancy if constant below 18o C for the elderly or high heat exposure from heat waves. (Barnett, n.d)
Humans experience comfort in different ways these include air temperature, humidity, air movement, radiant temperatures, physical movement and clothing worn.1 Ways to achieve comfort is through: Evaporative cooling “utilises... cross ventilation breezes and fans to evaporate sweat off our skin, which cools our bodies in the process of liquid turning into gas”.1 High humidity levels will decrease our comfort and evaporative cooling performance decreases as humidity of summer weather increases. Refrigerant Cycle Cooling - ‘heat pumps’ enable us utilise cooling and heating modes. They generally have efficiencies of 3.5-4.5x. This type of cooling dehumidifies indoor air as it operates, allowing us to stay comfortable at higher air temperatures (Barnett, n.d).
