Tips to Achieve 7 Stars

The key to 7 Stars is good design, so work closely with your designer or builder, and remember to use a Registered Building Practitioner. Using good Passive Solar Design from early on is the best way to achieve 7 stars. 

                                                                                                                                          

Options to Improve the Buildings Energy-Efficiency are;

 

Orientation

Orientation of the main living areas towards the north, to allow maximum sunlight when needed for warmth, and to exclude the sun’s heat when it isn’t needed. Carefully selecting your site so your home’s orientation takes advantage of solar energy can help you achieve up to 1 Star of your rating.

 

                                                                                                                                                 

 

Insulation

Insulate the walls, ceilings and suspended timber floors to reduce heat losses in winter and heat gains in summer; insulation is a very cost effective means of improving a building’s performance. Ceiling insulation recommended is R3.5 +, External walls R2.5, internal walls attaching to non-habitable rooms such as Garages, laundry R2.5.

 

Thermal Mass

Design your home to complement its construction. Houses with concrete slab floors and those with suspended timber floors each perform differently in summer and winter. For example, carpet can provide timber floored homes with extra floor insulation for warmth in winter whereas tiles on a concrete slab will make it easier for the floor to store solar energy collected through good passive design. Thermal Mass to store the heat from the sun when its required, and provide a heat sink when we need to be cooler.

 

Ventilation

Consider the internal layout of your home to enhance energy efficiency, such as locating windows opposite one another to capture cool fresh breezes and maximise cross ventilation.

 

Early design involvement 

Get in early with your Thermal Performance assessor early in the Design phase.

 

Improve the glazing: 

The cost of double and triple glazing has reduced considerably in recent years and there are thousands of options now available.

 

Increase Zoning:  

By including more internal doors in the design, mechanical heating and cooling estimates in NatHers can be applied more accurately. Places to include doors may be end of corridors, the bottom of stairs or close off occasionally used rooms, like living, rumpus and media rooms. 

 

Plan for fans:  

Including ceiling fans in all rooms will not only improve your NatHers rating but the homeowner's comfort. 

 

Check your colours:  

You can improve your rating by lightening external roof and wall colours for all except Climate zone 8 (Alpine).

 

Look at lighting:

Use IC4 rated sealed down lights. This makes for fewer ceiling penetrations and allows for continuous ceiling insulation. 

 

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Glazing

Utilize windows to improve energy efficiency through attention to size and location, and by making use of the large range of high performance energy efficient glazing products on the market. Glazing (windows) used to trap the sun’s warmth inside the house when it’s needed, and otherwise, to shade and protect the house from unwanted heat gain or heat loss (shade western windows in summer).

Sealing The Building Envelope

Draught-proofing and seeling of the building's envelope (eg: all external doors and windows)

Shading

Shading, Minimise western windows and eastern windows or shade appropriately. Make better use of the sun by shading windows in summer with eaves, external blinds and tailored landscaping.

Energy Efficient Lighting

Install energy efficient lighting, the more energy efficient the greater the savings you will achieve.

Other Options

Install the best available water-saving showerheads, taps and fittings.

 

 

Tips for Building 7 stars

 

Building for 7 stars doesn’t have to be costly or complicated. Simple design features and material choices make a big difference to energy efficiency and the rating outcome.

 

1) The  most important first step is to get your NatHERS assessor involved early in the design process. NatHERS  accredited assessors are extensively trained to improve ratings and providing options to get to 7 stars and beyond. 

 

2) Orientation is key: Build for the local climate, allowing shade and solar access as appropriate for tropical/temperate/cool climates. Repositioning a house plan on the block can make a world of difference to it's performance. See https://www.yourhome. gov.au/passive-design/orientation.

 

3) Improve the glazing: The cost of double and triple glazing has reduced in recent years and there are thousands of options now available. NatHERS includes both default and custom window options. Choosing

defaults will usually result in a lower rating, so switching to a custom window where all the specifications are known allows for greater flexibility. Window sizing, placement and shading are also important considerations and should suit the climate. See https://www.yourhome.gov.au/ passive-design/glazing to find out  more.

 

4) Increase zoning: By including more internal doors in the design, mechanical heating and cooling estimates in NatHERS can be applied more accurately. Places to include doors may be at the end of corridors, the bottom of stairs or to close off occasionally used rooms, like media and rumpus rooms.

 

5) Insulate more: Depending on the climate, ratings may  be improved by increasing

the R value of wall, floor and ceiling insulation or extending insulation to new areas e.g.  slab  edge, underneath the slab, the garage wall and internal walls (especially to unconditioned zones, like laundries and bathrooms). Care must be taken to not increase condensation risk. For more information, see www.yourhome.gov.au/passive- design/insulation, www.yourhome. gov.au/passive-design/condensation and www.abcb.gov.au/sites/default/ files/resources/2022/Handbook- condensation-in-buildings-2019.pdf.

 

6) Plan for fans: Specifying ceiling fans in all rooms will not only improve your NatHERS  rating but the homeowners’ comfort.

 

7)  Check your colours: Rating improvements can usually be achieved by lightening external roof and wall colours for all but NCC climate zone 8 (Alpine). If your software is able to do it, adjusting window frame colours can also  make a surprising difference. Talk to your clients about their choices early.

 

8) Look at lighting: NatHERS rewards homes with fewer ceiling  penetrations with higher ratings. Consider whether your  design can delete downlights that aren’t IC4 rated, roof windows and skylights and replace these with other lighting options that allow for continuous ceiling Insulation.


 

Design Strategies For Melbourne (Mild to Warm Summer, Cool Winter)

  • Moderate to high thermal mass for summer and winter (earth integrated if possible) - reduce thermal mass if solar gain is limited
  • Ample shade north facing solar gain all autumn to all spring
  • Access to cool breezes, ceiling fan ventilation
  • Protection from strong summer and winter winds
  • Moderate to high insulation levels
  • Light-mid colour roofs
  • Deciduous plantings for summer shade and winter solar gain
  • Moderate eaves and shading
  • Covered insulated roof, meshed outdoor living areas
  • Control infiltration path