O3 Ozone residential development in northwest Brisbane
3 Osborne Road, Mitchelton
This brand-new residential development in Brisbane’s Mitchelton contains twenty apartments, all with two bedrooms, split across six storeys. With overall dimensions of 50x18m, the property also has a communal recreation area on level five and carparks on the ground floor. A small ‘hole-in-the-wall’ commercial tenancy is located at the front of the building.
Using the whole property footprint, the ground floor has a 1:20 ramp towards the rear of the building. Along the north and south boundaries, retaining walls up to 1.2 metres high were used. On the eastern boundary, the walls are set back four metres where the ground floor level is higher than the natural ground.
A development application condition placed by the Brisbane City Council required the building to be set back three metres from the north and south boundaries. However, approval was granted for some vertical supporting elements along the boundary. One metre wide strips of the Level 1 transfer slab acted as beams to bridge the carparks to the boundaries. For the upper levels, masonry block walls were selected as the main load bearing elements due to their strength and cost-effectiveness.
Screw piles were selected for the footing system to achieve a rapid and cost effective solution for founding through existing fill and soft alluvial sandy clay soils.
The project used around 10,000 cubic metres of concrete and approximately 500 tons in steel. The overall project cost was $5 million.