Glazed Paradox—River Rocks House in the Tamar Valley

The River Rocks house is a set of contradictions and paradoxes, but never compromises. It is minimal, yet monumental, integrating both raw and highly refined components (“steel columns, glass, soil and rocks [are] used in their raw forms”). And, while it may seem at first to stand apart from its landscape, the connections are deeply set, says its Victorian-based architect, David Luck.

The house is an homage to David’s past. He grew up in the outer suburbs of Launceston, just to the south of this site, and although having moved away, never lost respect for, or connections with, the region. As a child, he spent time on a local family farm, and always remembered seeing odd houses along this reach of the river. He was “bewitched by these modernist expressions”, one of which was architect D. Graeme Lumsden’s donut-shaped courtyard house (1955) in Dilston. This house is now being lovingly restored by another devotee of Tasmanian modernism who, when visiting River Rocks, describes the process of slowly driving down the 300-metre-long driveway, catching occasional glimpses of the house between tree trunks, as highly intriguing. This experience is replicated inside the house by a forest of carefully-spaced steel columns through which the grey-blue Tamar River, and its valley, can be seen.

River Rocks is also a tribute to the architect’s loved ones; those he has lost. David’s parents died around the time of construction and this house is a memory tomb – he likens it to the Taj Mahal built by Mughal emperor Shah Jahan for his favourite wife, Mahal Mumtaz. “River Rocks is a white and black transparent monument to my parents’ memory … when excavating the ground for strip footings, my hands were in the same earth that my father was buried in nearby,” he says.

David takes care to explain River Rocks’ name. The 1.2-hectare site has remnant, endemic scrub punctuated by lichen-covered basalt shards. Basalt slabs (once lava flows) also tilt at the river’s edge; this is a region of very old and significant rock formations. During construction, 80 boulders were unearthed and later placed in the garden to match the construction grid. David now equates this placement with the standing stones of the Anglo-Saxons, or the stone gardens of Zen temples, such as Ryōan-ji. In his case, it is “a field of stones that stitch the home back into the earth”.

Two separate 125-square-metre living areas (each comprising a multi-use area, a bedroom and bathroom) are covered by a 450-square-metre flat roof. Straight and curved verandahs, which follow the roofline and encircle the entire house, can be manipulated to control the amount of solar gain internally, and create external microclimates.

Unsurprisingly, River Rocks has no window or door frames. Shadowed glass panes reflect the building structure and reinforce the columned sense of enclosure as metaphoric forest. Slicing through the grid of columns is the glazing system: toughened, double-glazed low-E, achieving a 6-star energy rating. Metre-wide double-glazed units are joined directly to the steel columns using structural glazing tape.

Fire-resistant silvertop ash verandah decking addresses the BAL 29 rating and the few external walls and doors are clad in screw-fixed flat-sheet metal panels. Apart from the plumbing and electrical installations, David constructed the entire house himself. The steel framing was delivered in eight-metre-long sections, then docked on site, welded and assembled. This self-build was an important method of deeply engaging with the site – and understanding its particular character. He did grapple with the sustainability of using so much steel and glass, but reconciled this by designing and constructing it for disassembly and component reuse.

Ninety tonnes of local plant-seeded topsoil were removed from the house site and driveway, then lifted back onto the roof, the weight of which is supported by 250 columns, arranged in straight lines on the uphill side, and curved on the downhill river side. “The result,” says David, “is a fantastically heavy-looking, grown-over construction.”

At River Rocks, all internal climate conditions are carefully and passively controlled by the verandahs and roof, and David wanted all components of the house to be clearly legible, and relatively easy to use, or replace. The internal spaces are deeply comfortable; a set of delightful experiences that provoke the inhabitants’ rational and fanciful contemplations. But, perhaps most importantly, the house has profound and emotionally-imbued connections with its ancient, and familial, landscape.

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