A new weekender designed by Devonport-based Starbox Architecture reimagines the no-frill Tasmanian beach shack, with the classic design getting a successful sustainability makeover.

Built by ET Construction, the Hawley Beach House project in Tasmania meets the client’s brief for a weekender that employs sustainable design principles.

Architect Jaron Coward explained that the clients lived about an hour and a half away and built the house as a weekender. “So they didn’t want to arrive on a Friday evening, walk into a cold house and have to crank up the heating.”

The new beach shack explores shack living in a modern way, without losing the characteristic simplicity that is the hallmark of this style of coastal holiday home.

The Starbox design employs passive solar principles – including the use of an exposed, polished concrete floor slab – to regulate the internal temperature and reduce energy costs. The client was on board with the concept of passive solar design right from the outset. The choice and positioning of building materials and the overall orientation of the structure are critical in passive solar design.

There are two distinct zones within the home – the kitchen/living area along the northern (front) elevation, and bedroom/bathroom/utility zone on the southern side.

The former is encased in double glazing on three sides, which helps maximise the ingress of the sun’s warmth to heat the interiors during the colder months.

In winter, when the sun sits low in the northern sky, a north-facing glass façade invites the sun’s warmth inside.

However, this energy has to be stored and then released throughout the day and into the night – that’s where concrete comes into its own.

Concrete floors and walls have high thermal mass. They effectively ‘bank’ the heat energy and then release it slowly, warming the interiors.

In summer, when the sun is overhead and the glass façade is protected by eaves, concrete helps maintain a stable, comfortable internal temperature, assisted by cross ventilation.

The stackable glass doors and windows in the Hawley Beach shack are positioned so they can be opened to encourage natural airflow to cool the space.

While the newly built home is yet to experience a full summer, its performance through the current winter has been nothing short of outstanding, according to Coward.

“We were there recently to take some photos, and the ambient temperature inside at about 6pm was beautifully warm,” he said.

The concrete slab is fairly typical for the site and engineering requirements – 100mm with thickened edges and R1.8 ClimaFoam Extruded Polystyrene (XPS) ground insulation. The top of the concrete slab has been polished and exposed as a hardwearing, low-maintenance flooring solution.

The external paths and driveways servicing the separate two-car garage are also in-situ concrete with exposed aggregate finishes.

The non-glazed external wall sections on both the garage and main dwelling are clad in Pacific teak. The Beach Shack at Hawley Beach preserves the underlying simplicity, but with a fresh and decidedly sustainable twist.

Main concrete elements:

  • In-situ polished slab floor
  • External paths and driveways servicing the separate two-car garage

Benefits of using concrete:

  • Thermal mass to help naturally regulate internal ambient temperature
  • Durability and low maintenance

Photography: Think Creative