Sustainability in Design 

Building with the environment in mind, both internal and external to build a healthier, dryer and warm interior environment are key considerations when looking to build.  When approaching any new build or renovation we place importance on creating a home that is built to last a lifetime and built for any circumstance in life.

Our team are skilled in calculating the thermal envelope of the building and can advise on changes to decrease heat loss and advise on improvements to the homes interior environment.  We are experienced Homestar Assessors, both design rating and built ratings. 


Homestar is a points based qualifying tool Homes (new builds and renovations) which has 4 main categories to provide the best thermally performing home within your budget:

  • Efficient: Rewards smaller dwellings and smaller footprints
  • Health and Comfort: These points reward attributes for occupant thermal comfort by way of whole house thermal performance, ventilation, moisture control and lighting. It also recognises interior finishes that minimise the detrimental impact on occupant health from products that emit pollutants such as volatile organic compounds (VOC’s)
  • Liveable: Rewards safe, secure and adaptable dwellings
  • Environmentally Responsible

Homestar ranges from Homestar 6 rating (60 points minimum) upto 10 Homestar rating (100+ points).  There are mandatory minimum requirements within each rating.

We work with you during the concept stage of your home to apply all the aspects of Homestar and sustainable design into the project knowing with the expert knowledge knowing where exactly you can improve the thermal envelope.


If we have not designed your home we can still assess your plans in order to determine the requirements you need to achieve a homestar rating.  This information required to do this includes construction details and specifications. We specifically look at the requirements and calculations for the heat loss of the home, calculating construction R values and thermal bridging.  We model the units in the ECCHO tool which gives us data on the performance of the home.

We can provide you an estimate of how your building is performing and put forward some recommendations to you should it not achieve what you set out for.  Should the project look to be on track in terms of Homestar targets we can continue to provide all the data required and submit on your behalf to NZGBC who we continually work with.


We work with you and the builder to provide evidence required by NZGBC to determine Homestar design rating information had been adhered to including verifying construction timber members sizing and spacings and insulation R values.  Will also include verification of windows sizes and openings, materials and fixtures etc to validate the design rating evidence.  Site visits would be required in the determining the evidence but also receipts, invoices and photos may be accepted to assist the evaluation of the rating.

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