Case Study

Stockton Duplex


In-Haus Living

Opting for a design that takes advantage of natural air flow through cross ventilation, and colours that help absorb or reflect the heat are some of the key characteristics that improve the overall thermal performance of these dwellings. 

Designer: Torren Bell Building Design 

Location: Stockton, Newcastle NSW 

NCC Climate Zone: 5 – Warm Temperate 

NatHERS Star Rating: 6 Stars 

BASIX: Deemed to Satisfy Compliance  

Solar: 3Kw per dwelling  

Rainwater Tanks: 5000L per dwelling 

The Design



Designed by award-winning Building Designer Torren Bell for Inhaus Living, a licenced building company based in Sydney. 

‘Inhaus Living’ – an idealist who dreams of living in a harmonious world. 

Enjoying an unprecedented setting in Stockton, one of Newcastle’s most sought-after locations, these chic two storey beachside dwellings overlook breathtaking panoramic views east from Port Stephens to Nobby’s Lighthouse and headland. 

Demolish and Rebuild

The developers of this property sort to demolish the original out dated one-storey, 3 bedroom red brick home replacing it with two by two storey, four bedroom dwellings each boasting a swimming pool and uninterrupted views across the bay.  

Climate Considerations

Australia has 8 main climate zones, as defined by the National Construction Code (NCC 2019). Each of these climate zones has different design and construction requirements.  

Newcastle falls into the NCC Climate Zone 5, which is a warm temperate described as having four distinct seasons. Although summer and winter can exceed human comfort range, spring and autumn are ideal. 

Residents can expect to experience cold to mild winters with low humidity and hot to very hot summers with moderate humidity.

Given both summer and winter can exceed the ‘human comfort range’ it is important to ensure each dwelling is protected from unwanted solar gain throughout the summer months, but also able to receive the warmth of the sun during the winter months. 

These are important factors that must be considered by all parties during the design process. 

NatHERS Assessment Results

Thermal performance is the amount of heating or cooling that makes the interiors of a home comfortable. In other words, it is a measurement of how efficiently your home can retain heat. A building with good thermal performance will need less energy to keep the insides warm and comfortable. (CSIRO)

Thermal Performance Solutions

Opting for a design that takes advantage of natural air flow through cross ventilation, and colours that help absorb or reflect the heat are some of the key characteristics that improve the overall thermal performance of these dwellings. 

The design team for this multi-million dollar project have opted to use a combination of dark and light colours for the north-west facing dwelling and stand-alone light colours for the south-east facing dwelling.   

Colour Schemes

When undertaking a NatHERS Thermal Performance assessment, assessors are required to nominate the colour of the external walls and roof elements in the software tool. 

The chosen colour of the external walls and roof is represented by its solar absorptance value, a decimal number that is an indicator of the colour’s ability to absorb radiation from the sun. 

“Absorptance, (α), is a measure of the ability of a surface to absorb radiation. It is the ratio of the thermal radiation absorbed by a surface to that absorbed by a perfectly absorbing surface”, and “Solar absorptance, refers to the ability of a surface to absorb all the radiation wavelengths of the sun’s emission spectrum”.   Dr Holger Willrath of Solar Logic.

Australia in 1950

Our buildings’ colour palette today is very different to that of 50 years ago. The Australia of the 1950’s & 60’s encompassed lots of red brick walls and dark coloured roofs, reminiscent of the colours of a much colder climate. 

The changes we are encountering today are part of a natural process of evolution of trends in our society, but to a larger degree reflect the adaptation of our building designers to better suit the Australian climate, as well as our greater awareness of the impact this will have on the health of our environment.  

Colour schemes can greatly impact the cooling or heating loads attributed to a residential dwelling and must be considered to accommodate the applicable climate zone. 

The Waffle Pod Slab

The design team were open to using the waffle pod slab as an alternative to the traditional ‘concrete slab’.  

Here’s why: 

The Waffle Pod Slab system is an innovative method of constructing concrete slabs, providing enormous strength and durability, and significantly reducing building costs.  

Built ‘on-ground’ rather than ‘in-ground’, the Waffle Pod Slab eliminates the need for labour intensive trenching – which is required in conventional concrete slab construction methods. Construction takes place on cleared level surfaces, allowing work to continue uninterrupted in wet weather. And Waffle Pod Slabs allow a more accurate specification of concrete quantities.   

This results in: 

  • Reduced waste 
  • Minimal impact on the environment 
  • Less soil disturbance 
  • No excavated rubble from trenches to dispose of. 


The on-ground slab, with air pockets created by the Pods, forms an insulating layer between the structure and the ground. 

Construction Assembly 

The following insulation solutions were applied to the construction assembly for this project.,, 



Household Features