Rather than following business as usual and clearing the block, this progressive owner decided to keep the original “Californian Bungalow” and add an extension to provide a stylish, comfortable and sustainable 4×2 family home. Saving a fantastic 105% against the benchmark also enabled this design to achieve a platunim rating and take home eTool LCA winner of the year 2011.

The summarised results of this project:

Total CO2e / Year / occupant (kg CO2e)% Saved Against BenchmarkeTool
Materials34677 %
Assembly, Transport and Recurring Impact23472 %
Operational Carbon-1,000118%
Total Carbon-420105 %

Project features

The materials and construction savings associated with being able to “re-use” the entire front of the building, combined with the use of low embodied energy materials for the extension resulted in a very low embodied energy component for this assessment.

With additional insulation to the roof, and some parts of the walls and floors, and carefully positioned glazing they achieved high thermal performance for this design. The house is equipped with a Solar Hot Water system with a gas instantaneous boost to provide the most efficient form of water heating for the family.

To cap it all off the owner has installed a 5.7kW Solar PV grid connect system to produce more energy than the house will need and feed substantial amounts of power back into the grid to offset even more carbon. As a result of offsetting this large amount of energy and carbon the design is actually considered “Carbon Negative”.

Please contact eTool to arrange a cost effective assessment or training on how to achieve best practice in low carbon building design.

This assessment was conducted by Richard Haynes