At a height of almost 45 metres, 25 King will be the world’s tallest engineered timber office building when completed in late 2018 as part of the RNA Showgrounds redevelopment in Brisbane’s Bowen Hills.

The use of CLT (cross-laminated timber) and Glulum (glue-laminated timber) in high-rise construction represents a growing trend around the world, and one that is making significant headway in Australia.

Following the construction of Sydney’s International House at Barangaroo, Lendlease is now building its fifth engineered timber building in Australia as part of the redevelopment of the Brisbane Showgrounds precinct.

Designed by architect Bates Smart and owned by Impact Investment Group, 25 King is set to be the tallest engineered timber office building in the world once completed in late 2018.

As well as providing the structural strength of traditional concrete and steel, the use of these engineered timbers will dramatically reduce the building’s environmental impact. CLT has a far lower carbon footprint than other building materials, is produced with zero waste from timbers sourced from certified sustainably-managed forests, and can accelerate the speed of construction.

The timber construction will be combined with a fully glazed façade to maximise daylight penetration across the building’s nine office levels, while sun shading on the western and eastern façades will reduce solar heat gain.

But 25 King’s sustainability commitments are more than just skin deep.

The project is designed to meet the Property Council of Australia A-Grade compliance, and is targeting a 6 star Green Star rating using the new Design and As-Built v1.1 tool. A 5 star NABERS Energy rating is also being targeted.

Critical to achieving these ratings will be the energy performance of the building’s mechanical services and HVAC design.

Following a period of value management of the Aurecon design – themselves a key tenant of the new building – A.G. Coombs was appointed by Lendlease as mechanical contractor on the project.

The building’s 14,000m² NLA of A-Grade office space will be conditioned by an energy efficient, low-temperature variable air volume (VAV) system, supplied by central air handling units (AHUs) on the roof.

The chilled water plant will comprise of two water-cooled, variable speed drive (VSD) screw chillers with variable primary chilled water pumping.

Outside air preconditioning will be achieved using energy recovered from spill and toilet exhaust air via energy reclaim wheels.

A single level basement, to accommodate 56 cars, will also be mechanically ventilated. This level will feature electric vehicle charging points and racks for 152 bicycles – as well as end-of-trip facilities.

The use of BIM (Building Information Modelling) will be integral to the services fit-out at 25 King, and the A.G. Coombs team is taking the lead for all building services with BIM coordination.

BIM will the used to ensure the accurate position of penetrations in the building’s prefabricated CLT structural elements, and to provide high level coordination of building services – all of which will be exposed and require a high level of detail in their installation.

A.G. Coombs will employ a number of specialist methods during construction to achieve these outcomes, including prefabrication
of plant rooms, risers and horizontal modules where possible.

25 King represents a world first in engineered timber construction, and we are pleased to be working with Lendlease helping to deliver what will be a wonderful achievement for the Brisbane Showgrounds precinctDanny McGregor, Queensland Manager,
A.G. Coombs