The Brisbane City Council has granted approval for the redevelopment of a 135-year-old heritage building into a multi-use 30-storey commercial tower, just 9.5 metres in width. The building located at 320 George Street in Brisbane will likely be one of the narrowest high-rise structures in the CBD.

Designed by international multidisciplinary firm Hames Sharley, the building is owned by Lionmar Holdings, and will feature 9100sqm of boutique commercial office space, three levels of restaurant space, apartments and 17 carparks, with a rooftop bar above.

Hames Sharley principal Jason Preston, who heads the firm’s Brisbane studio, observed that the building’s narrowness demanded an innovative design to deal with the challenges of structural tension, compression and stability.

“At just nine and a half metres wide and 30 storeys tall, we believe this would be the narrowest building of a comparable height in Brisbane,” Preston says.

“Given the building’s four lifts are designed as a ‘side core’ to the west boundary wall, a building of this kind will twist and sway differently to a traditional tower, which is usually anchored by a number of central lifts, stair cores and a larger floor plate.”

The Hames Sharley team collaborated closely with Currie and Brown (project managers) and ADG (structural and façade engineers) to propose a hybrid ‘exo-skeleton’ bracing system for the building, both as a structural necessity as well as to visually anchor the building, with a typical continuous glazed curtain wall retained as the external skin.

Among the building’s highlights are a fine dining restaurant at the building’s base featuring a three-storey open view to the city to give diners an indoor-outdoor experience; a rooftop bar also offering prominent views across the Brisbane River to South Brisbane and through the CBD; and an expansive 400-square-metre city room and garden on level 14 for the tenants’ enjoyment.

Due to the building’s heritage listing, the façade will be restored under the expert guidance of heritage architect Malcolm Elliot from Vault Heritage Consulting. Most of the interior heritage features were gutted in the 1980s when the building was rebuilt internally, says Preston. The original brickwork, which has been covered in plaster during one of the past renovations, will be restored by peeling back the layers of render.

The modern office tower is expected to earn premium A-grade commercial development status due to its sustainability characteristics, high-end lobby finishes, express lifts and high-performing services.

Construction of the building is likely to start before Christmas 2019.