Achieving NatHERS 7-star compliance for new homes in Sydney requires a high degree of expertise and careful consideration of numerous factors.
Key Factors in Design: Site Orientation and Shading
Critical elements such as site orientation, narrow blocks, and shading from vegetation or adjacent structures must be meticulously evaluated. These considerations are paramount in harnessing the sun’s movement to enhance energy efficiency and ensure year-round comfort.
Harnessing the Sun’s Movement: Seasonal Strategies
Summer Considerations:
High Sun Trajectory: Shield northern windows from the intense midday sun using eaves or window hoods.
Minimize East/West Exposure: Reduce or shade eastern and especially western windows to mitigate the harsh afternoon sun, employing vertical shading solutions for optimal protection.
Winter Considerations:
Low Sun Path: Maximize sunlight and warmth by designing with north-facing windows, reducing reliance on heating systems.
Optimal Orientation: East-West Alignment
A fundamental design principle is to align the house’s longest axis along the east-west direction. This maximizes winter sun exposure while minimizing direct sun during summer. Position living areas and kitchens towards the north/northeast for abundant natural light, while placing service areas to the west/southwest and studies/bedrooms to the south.
Design Solutions for Challenging Environments
Designing for non-north-facing rear orientations poses unique challenges. Homeowners desire living areas and kitchens that seamlessly connect with backyards and receive ample natural light year-round. However, the lower winter sun trajectory can cast longer shadows on south-facing backyards, influenced by the upper floor's height and configuration.
To address these challenges, several design solutions can be implemented:
Summer and Winter Living Areas: Create seasonal living spaces.
Courtyards and Voids: Integrate outdoor spaces within the home's design.
Stairwells and Skillion Roofs: Utilize vertical spaces and angled roofs for better light penetration.
Celestial Windows and Skylights: Incorporate high windows and skylights to enhance natural light.
However, it's important to note that some solutions, such as voids and high glass-to-floor ratios, may impact the achievement of a 7-star rating, especially in southern elevations where living and alfresco areas are typically located.
Expertise in Non-Ideal Orientations and Shading
For homes with non-ideal orientations, narrow blocks, or significant northern shading, skilled design is crucial. This often involves integrating landscape design to balance aesthetics, functionality, and energy efficiency. Meeting NatHERS 7-star compliance in such scenarios demands meticulous planning and expert craftsmanship to create a comfortable and sustainable living environment.
Engaging a Custom Home Designer/Builder
The complexities of unique site challenges necessitate the expertise of a custom home designer or builder. Standard designs rarely achieve the desired outcomes for natural light and comfort, especially in knock-down rebuilds with distinct site characteristics. The 7-star requirement intensifies these challenges, impacting budgetary considerations.
In summary, designing energy-efficient homes that meet NatHERS 7-star compliance is a sophisticated endeavour. It requires aligning with the sun’s natural movement, addressing unique site conditions, and balancing aesthetics, functionality, and energy efficiency. Only through the expertise of custom home designers and builders can homeowners achieve a comfortable and sustainable living environment that harmonizes with natural elements.
Comments