While the triangular-shaped site has been thoughtfully expanded over the years, there was a small pocket of development in the 1960s that "under delivered" in quality. "They were fairly ordinary buildings, a hostel and nursing home that were quite prosaic," says architect Peter Williams, director of Williams Boag Architects.

Williams Boag Architects was commissioned by the Old Colonists' Association to replace the hostel and nursing home with 25 independent and assisted living units, of a quality that would respond to the estate's architectural legacy. The architects came up with a scheme for one- and two-bedroom units (the two-bedroom units allowing for a carer to stay). But creating an institutional style building was the furthest thing from their minds. "We wanted the design to respond to the surrounding buildings. It is such a rich architectural setting. But we didn't want to create a pastiche-style. It had to be representative of its time, without playing 'historical games'," says Williams, who found the heritage authorities, such as Heritage Victoria and the City of Yarra, highly accepting of their scheme.

Williams Boag started by selecting a variety of bricks for the new two-storey housing wing. Many of the historical brick homes on site feature a number of brick types. Three different coloured glazed bricks were selected, together with a slender Roman-style brick, to add depth and texture. The architects also included a series of concrete sills in response to the sills appearing in many of the 19th-century homes.

"Many of the period homes have foundation stones under their front windows or set within a gable. You can see who the original architect was, and in some cases, who donated the money to build these houses," Williams says.

The horseshoe-shaped community building, which wraps around an established elm, features these striations of bricks. "We had to build around the tree. But we also wanted to create a sense of arrival," Williams says.

The community building includes a kitchen and dining area, together with a large area for presentations and meetings. "In a sense, this building acts as an anchor to the site," he says.

And contrasted with the solidity of the brick facade is a highly glazed northern elevation, offering views of the landscaped grounds. To diffuse the northern light and create privacy, a series of chunk timber battens line both the community hall and the living wing. The timber also creates a sense of warmth, akin to a home-like setting. "There is a certain Scandinavian feel in the design. We wanted these units to feel like home, rather than an institution".

The units, located on both the ground and first floor, are loosely delineated into dependent living and independent living, with a stairwell bridging the two. Varying in area from 55 square metres to 80 square metres, the rooms are light-filled and carefully designed to accommodate wheelchairs (large sliding doors between rooms). And rather than create shotgun corridors through the building, the circulation spines appear on the periphery, allowing those in their living areas to connect with other residents walking past.

The Rushall Park estate is a fine example of architectural integrity, where architectural styles from the past are as valued as contemporary architecture. "It is a small pocket of Melbourne's architectural history. And that meant creating something that would be as valued in decades to come," Williams says.