Biv Punakaiki

Entrant: 
Fabric Christchurch

Category: 
1. Residential design award for single family dwelling

Photographed by: 
Stephen Goodenough

Designed as a collaboration between a New Zealand based architect and the client who is a Kiwi architect based in Hong Kong, this building was to be rented as high end, short term accommodation; and is the first of a series of buildings intending to use architecture as a way to attract and delight visitors.

Nestled in the Punakaiki bush, the response is a reinterpretation of the historic gold miners huts local to the area. The form of the building takes cues from the exterior chimneys repeated on those huts. Internally the central skylight represents the top of a smokestack, while the large windows offer views into the bush or the cliffs beyond for an all-encompassing West Coast experience. The balance of minimal but luxury facilities are just enough to keep the focus on simple living, while still remaining comfortable and memorable.

A full timber structure and interior in the form of cross laminated timber (CLT) was chosen to represent the historic miners hut aesthetic. But unlike an old hut, this building’s passive thermal gain and highly insulated construction, along with an active ventilation system, ensures it maintains stable internal and surface temperatures with no need for human input to remain comfortable. This lowers the running cost to almost zero and ensures all guests are welcomed by a cosy environment on arrival.

Along with low energy input, low embodied carbon while maintaining durability was an important factor in material selection, with the CLT offsetting the higher carbon of the more durable and higher thermal mass concrete floor and corrosion resistant aluminium cladding. This sequestering of carbon by the CLT largely reduces the overall embodied carbon in the building - this is calculated at 47tCO2.

Prefabricated mass timber construction made building in this remote location efficient, enabling us to promptly enclose the structure, which was crucial in the rainy environment.

All detailing was to be as minimalist as possible to blur the line between interior and exterior, therefore drawing guests further into their West Coast experience. Above the floor, the full CLT structure is wrapped in 50mm Kingspan insulation and a vented cavity with European aluminium cladding. The geometry of the CLT structure and how this relates to the exterior aluminium envelope was a challenge in the design process and critical to get right to ensure elegant detailing on both the interior and exterior faces. The use of CLT played an essential role in the ability to achieve this.