A three-storey single residence bordering Adelaide City parklands traverses its planning overlays with stealthy “snail”-like geometry.

Despite taking colour cues from its leafy context, Treehouse stands out on its street corner in the affluent suburb of North Adelaide, flanked by a medley of heritage frontages. 

The material and colour palette takes inspiration from nearby parklands.

The project arrived at Adelaide-based architecture and design practice Das Studio as a “distressed project”, according to architect and managing director Dino Vrynios. Clients Bob and Ann Crago had rejected proposals from four different architects who weren’t able to secure council approval for their brief. Das won the bid to transform the septuagenarian couple’s 1970s brown-brick townhouse into a “modern, stylish, functional home”.  

“Some of the delay was related to our desire to ‘push the boundaries’ in relation to the design,” the Cragos tell Australian Design Review, adding council “knockbacks”, heritage limitations, SA Water easement regulations and escalating costs also played their part.

The front façade of Treehouse.

Flipping and lifting the layout

The original home fit two levels and a small roof space onto a compact site. Vrynios says the Das team used “strategy” and “stealth” to navigate the planning overlays and expand the existing form into a three-bedroom dwelling that the Cragos’ two adult children and kids could visit at any time.

“All the living spaces were on the ground floor, which was incredibly dark and dingy,” Vrynios explains. “The bedrooms were on the upper level.”

The two-bedroom house before renovation. Photo: Supplied.

Recognising that the guest bedrooms would be used only occasionally, the designers “flipped” the layout, positioning them on the ground floor, which has been designed to allow guests to function independently from the rest of the home. From there, Das lifted the new open-plan living and dining areas up to level one. “Then we were able to make the case to Council that if we maintained the roof form from the frontage, we could embed a third level,” Vrynios says.

While it took hard work to design, it was “always clear” to Das to maintain the frontage treatment because of how it related to the adjacent heritage cottages. The studio recognised quality in the shapes of the existing home, as well as the opportunity the rear provided to unlock a third level that did not overshadow the neighbours. 

A central window strip in the original building became a logical break point for the new third level, which now contains the master bedroom and bathroom. Viewed from the side street, this level is covered by timber screens – a material deliberately distinct from the rest of the house, making the third level less imposing.

“It is like a snail; it’s a bit of a weird shape,” Vrynios says. “It’s funny how buildings end up taking on personas of animals.”

An existing window strip became a break point for the third level.

The design also had to contend with an SA Water easement that technically restricted construction within three metres of the rear boundary, should SA Water need to access the area for works. Das’ solution was to design a completely removable garage structure with an outdoor deck on its roof that catches the morning sun.

“The client took a calculated risk with us on that,” Vrynios says. 

‘Hard-working’ indoor and outdoor spaces

In addition to the small front garden and the back deck above the carport, there are two other outdoor spaces at Treehouse. A small balcony for the Crago couple hides behind a timber screen on the third level, while a front-facing balcony on the second level receives the afternoon light. Skylights open up over a three-level staircase that runs up the whole side of the building.

A small balcony hides behind a timber screen on the third level.

“Wherever there was a nook, we put storage,” Vrynios says, referring to a toilet tucked underneath the stairs and a retractable desk on the second floor, as well as a laundry/kitchenette on the ground floor. “It all looks like it works perfectly, but it was really hard work to fit the programming in with geometries of the house effectively.”

Das Studio worked hard to maximise the tight geometries of Treehouse.

“The townhouse sits on a 96-square-metre block and every square centimetre is used to maximum effect – even under the stairs,” the Cragos add. “The three-level lift adds to the future-proofing aspect.”

At the time of writing, the Cragos are living inside Treehouse, but issues with the builder have meant the interior vision has not yet been entirely realised.

The completed upstairs bathroom.

A ‘civic gesture’

Architecturally, Treehouse bears the hallmarks of a Das Studio project, including deliberate use of colour, strong geometry and bold forms, such as the large circular window on the master bedroom. 

A large circular window on the master bedroom.

Vrynios says the client embraced the design process and understood that their home could be a “great civic gesture” as much as a place for them to “live their best lives”. As the Cragos observe, frequent compliments from passers-by – who say the exterior “adds another dimension to the heritage area” – seem to validate this intention.

“There’s a strategy and purposefulness behind every decision to achieve not just the spatial programming, but to get a result for a client in a situation where they were stuck,” Vrynios says. “We felt like we validated the value of design on this project.”

Completed project photography by Anthony Basheer.

Related: View Nicolas Gutierrez’s soulful apartment conversion.