Attaining optimum thermal comfort in Australian residential buildings is necessary for obtaining a BASIX certificate. Sunlight access is one of the major contributing factors to the thermal comfort of any building. The building's passive heating and cooling conditions are greatly influenced by the amount of direct sunlight exposure the building is receiving.
However, with seasonal changes in the sunlight variation, determining the required direct sunlight for optimum thermal comfort of a building needs becomes difficult.
Attaining accurate thermal comfort is essential for developing sustainable buildings and reducing energy consumption. This is critical for commercial buildings and apartments to achieve a 5-6 star NABERS Rating.
Various construction design factors influence sunlight exposure to a building. Considering those factors can help develop an energy-efficient building.
Consider Sun Angle And Sitting
The seasonal sun angles vary with the latitudinal location of your building. The variation in the sun angles significantly increases when you travel further north or south.
Optimum positioning of roofs, eaves of buildings, window sills are required to account for this variation. This allows maximum exposure to direct sunlight during the winter season and limit sun exposure in summers.
For example, Sydney, located in the southern hemisphere (latitude of 34° S), experiences a seasonal variation of 45° in solar angle. Optimising your building position and roofing to the sunlight exposure helps it to get a good NABERS Rating.
A sustainable building design is the key to obtaining a BASIX certificate for single-dwelling or multi-dwelling residential buildings.
Consider Climate Specific Eaves and Window Shading
The angle and depth of the window shading and eaves determine the amount of sunlight entering the building.
Direct sunlight is beneficial during the colder seasons- early spring, late autumn or winter. Therefore shallower eaves and window shades allow a considerable amount of sunlight to enter the building, thus decreasing heating costs. However, the areas experiencing long or harsh summer months will benefit from deeper and thicker shadings.
The depth of the shading is also dependent on the wall orientation. To obtain an optimum NABERS rating, you may need to adjust the shadings for different walls and window placement.
Adjusting the thermal comfort for residential buildings delivers an excellent NatHERS rating; thus, obtaining a BASIX certificate becomes easier.
The shading requirements are also influenced by the size and height of the windows in the building. Larger windows from floor to ceiling, glazing will offer a much higher opportunity to receive direct sun during the daytime than shorter windows with the same shading depth.
Consider Window Placement And Glazing
The positioning of the windows and the glazing materials have a drastic effect on the thermal comfort of a building. It determines the heat buildup and escapes inside the buildings, thus determining the requirement of auxiliary cooling and heating systems.
Windows and glazings need to be adjusted according to the climatic zones. Warm climatic zones require windows with low solar heat gain coefficient to prevent unwanted heat gain and low U-value for good insulation. Similarly, for colder regions, high heat gain coefficient windows are more desirable.
Window placement and glazing assessments are necessary for obtaining a BASIX certificate.
