Infinity House

Infinity House, also known as the Curl Curl House, is a compact home in Curl Curl on Sydney's northern beaches, designed and built by CplusC Architects + Builders as an exercise in material, time and cost efficiency. The brief called for two bedrooms with built-in robes, a combined bathroom and laundry, an open-plan kitchen, dining and living space, and a deck, all on a single level extending from the carport and main entrance.

A shared driveway, a services easement and a tight site shaped the building envelope, allowing the internal floor area to be maximised without sacrificing outdoor amenity. At just under 100 square metres, every element of the plan has been carefully considered.

The curved form created the main construction challenge: working the building around the circumference of the narrow driveway. The curve was achieved using plywood top and bottom plates with closely spaced studs, and reads externally as a dark cedar sweep leading to the entrance. Because the shared driveway runs past the living areas along the eastern facade, privacy was a key concern. Openings on this side were kept to a minimum and fitted with removable cedar screens, oil-finished to add a warmer note against the black cedar cladding.

To compensate for the limited openings, a sinuous skylight runs the length of the eastern wall, drawing daylight into the living areas. Laminated veneer lumber (LVL) roof beams cross the skylight on a precise grid, turning a structural element that would normally be concealed into a feature.

The requirement for a single level led to the building being raised 600 millimetres above street level to meet the carport. This created room for a generous sub-floor water storage system and allowed clean, unobstructed spans across the living and private areas. Continuous-span LVL forms both the floor and roof structure, with the roof carried on a central spine. The spine supports the roof, stiffens the building and houses the service core, holding the wet areas, living-room joinery, wardrobe and storage, while separating the public spaces to the east from the private rooms to the west.

Built on a 259 square metre site to a modest budget and a 24-week programme, the result is a highly detailed home tuned to its brief, budget, climate and site.

The project was completed in 2011.

Architect and builder: CplusC Architects + Builders. Photography: Simon Whitbread and Murray Fredericks.