Description:

New Zealand’s traditional timber construction and detailing practices have defined the evolving expression of residential architecture in New Zealand, but this lightweight tectonic language has significant thermal performance issues. Low minimum performance standards in the New Zealand building code have resulted in a building stock of cold and damp houses. The project aims to tilt the existing aesthetic traditions of New Zealand residential architecture towards a language that performs better thermally, by producing architecture that combines the aesthetic traditions of our past, with high performing construction systems of the future.

“Thermal Tectonics” focuses on addressing the middle ground between the empirical and data-driven research fields of thermal performance, and the poetics of construction or architectural tectonics. The presented design for a New Zealand ‘Bach’ was informed by a tectonic approach to energy efficient construction, focusing upon developing a tectonic expression that is directly drawn from and reflects the novel properties of high performance construction systems. The resolved design aligns a prefabricated SIP system with the vernacular typology of the Bach, developing a detail language that connects the building to place without the need for extensive low-performing glazing.

The design process drew on Marco Frascari’s idea of the fertile detail, and iteratively developed key architectural junctions that informed the final design. Heat-transfer simulation was used to minimise thermal bridging, while modelmaking was used to gain a greater understanding of the constructability, and possible aesthetic expression of each junction. This approach creates an explicit relationship between building elements and their thermal function, by using thermal simulation software to generate tectonic diagrams that describe how building elements are configured to express thermal performance. This approach diverges from current design practices where thermal performance is considered when optimising details driven by other criteria.

The final design celebrates the warmth and texture of vernacular construction through the revealed internal structure, and unfinished surface of the structurally-insulated-panels. The overwhelmingly timber experience is evocative of early holiday homes in many of New Zealand’s coastal communities.

The internal spaces are separated into two complementary forms, in order to allow the architecture to be read as a collection of small sheds along the coast. The twisted roof form of the building is conceived as an abstracted gable, and emphasised by the continuous wrapping of the timber rainscreen, designed to age and weather as the building settles into the muted colours of the surrounding tussock and beach dunes.

The final design outcome demonstrates that thermal performance, and tectonic expression are not mutually exclusive pursuits. The tectonic qualities of alternative high performance construction systems offer many compelling expressions for sustainable architecture that can contribute to the evolution of New Zealand’s timber architectural heritage.